known chemical element symbol atomic number word comes swedish language directly translates heavy stone swedish order distinguish swedish alternatively named hard rare metal standard conditions found naturally earth exclusively chemical compounds identified new element isolated metal important include free element remarkable especially fact highest melting point elements high density times water comparable gold higher times lead hard material making difficult work pure single cut hard steel numerous applications including light ray tubes target radiation high density military applications penetrating projectiles compounds industrial metal transition series known occur species bacteria heaviest element known essential living organism copper somewhat toxic animal life characteristics physical properties raw form hard steel grey metal hard work pure retains exceeds worked easily worked drawing objects commonly formed metals pure form highest melting point lowest pressure temperatures highest strength carbon remains solid higher temperatures carbon considered higher melting point lowest thermal expansion pure metal low thermal expansion high melting point strength originate strong bonds formed small quantities steel greatly increases exists major forms body centered cubic structure stable form structure phase called cubic phase ambient conditions owing non synthesis contrary phase grains form exhibits habit phase electrical lower transition temperature relative phase mixing phases allows obtaining intermediate values value raised metal low temperature circuits naturally occurring consists half lives long considered stable theoretically decay element alpha observed half life years average yields alpha natural year naturally occurring observed decay half lives years years years years artificial characterized stable half life days half life days half life days half life days half life remaining radioactive half lives hours half lives minutes states stable minutes chemical properties attack oxygen common formal state exhibits states typically combines oxygen form yellow solutions form produced heating carbon resistant chemical attack strongly form solution gives neutral acidic conditions progressively treated acid yields time converts produces reached exists cluster oxygen known exist species inclusion different place central produces wide variety acid form compounds metals known example bronze history discovered new acid acid time named suggested possible obtain new metal reducing acid found acid identical acid later year royal society town spain brothers succeeded reduction acid credited discovery element world war played significant role background political dealings portugal main european source element pressure sides deposits ore desirable properties resistance high temperatures density strengthening important raw material arms industry constituent weapons equipment employed production cutting tools steel etymology swedish heavy stone english french languages element countries old swedish mineral european especially slavic languages derived mineral origin chemical symbol derived german wolf wolf wolf cream given turn derives element translates english wolf reference large amounts tin consumed mineral extraction occurrence found iron solid solution minerals calcium minerals moderately rare economical value include recently approved native production tonnes produced year world production tonnes main producers follows data tonnes additional production company information reserves tonnes considered conflict mineral mining practices observed democratic republic large deposit ore edge united_kingdom exploited world war world war recent increases prices reactivated extracted stages ore eventually converted heated hydrogen carbon produce high melting point commercially feasible cast instead mixed small amounts metals process producing extracted hydrogen reduction traded contract tracked exchanges like london metal exchange prices usually quoted concentrate converted metal equivalent kilogram applications approximately half consumed production hard materials remaining major use chemical compounds hard materials mainly production hard materials based hardest melting point efficient electrical conductor wear resistant cutting tools knives drills circular turning tools mining petroleum construction industries actually metal composite metallic acts binding matrix material hold particles place type industrial use accounts current consumption jewelry industry makes rings metal metallic metal composite rings use metal matrix place takes higher polished manufacturers retailers refer metal rings material extremely resistant hold finish longer rings metallic rings crack sharp blow density applied obtaining heavy metal good example high speed steel contain high melting point makes good material applications like rocket example submarine launched missile wide range different applications including automotive industries radiation containing turbine blades wear resistant parts armaments usually iron form heavy energy alternative depleted applications problematic depleted form additional properties required example ordinary small arms bullets designed penetrate body armor similarly cannon shells grenades missiles create dense metal explosives use dense powder reduce damage increasing explosives small radius chemical applications high temperature component commonly applications calcium widely lighting crystal nuclear physics nuclear medicine contain chemical industries incorporated selective reduction found coal fired power plants convert nitrogen nitrogen water helps physical strength catalyst extends catalyst life niche uses applications requiring high density include weights ballast tail ballast commercial aircraft ballast race cars nascar formula depleted purposes similarly high density blocks cruise balance mass devices entry vehicle portion mars science laboratory spacecraft ideal material use mass necessary good results achieved compact bar high density copper iron high quality allow smaller diameter fishing allow fly sink rapidly cello strings wound extra density gives sting projection buy string use strings different set reagent mixture different chemicals protein content analysis gold density similar gold allows jewelry alternative gold platinum metallic harder gold hard making useful rings resist especially designs brushed finish density similar gold dense gold bars plating bar gold observed 1980s taking existing gold bar drilling holes replacing removed gold rods exactly properties gold differ gold pass superficial tests gold available commercially china main source jewelry bars electronics retains strength high temperatures high melting point high temperature applications light ray tube vacuum tube heating elements rocket engine high melting point makes suitable high temperature uses electrical heating applications notably gas arc process called gas properties relative chemical tips electron beam instruments use field guns electron electronics material integrated circuits dioxide material metallic films replace conventional electronics coat electronic structure makes main sources ray targets high energy industry radioactive samples gamma imaging material coded excellent properties powder filler material plastic substitute lead bullets shot radiation shields element thermal expansion similar glass making glass metal seals biological role atomic number heaviest element known functional heaviest bacteria example called use similarly complex despite contain complex use living organisms typically reduce requiring discovered requires case pair function pairing requiring family employ known use version unusual reaction reaction mechanisms proposed direct interaction triple bond containing bacteria found contain non protein bound complex definitively described soil metal non imported organisms substitute certain effect action cases positive soil chemistry determines soils cause acidic soils cause lead studied effect lead found lethal low levels toxic completely reproductive ability studied biological copper antagonist role similar action found biological copper chemicals similar precautions rare compounds generally effects environment limited median lethal dose depends strongly animal method administration varies rabbits metal powder rats people exposed workplace breathing skin contact eye contact national institute safety health set recommended exposure limit hour short term limit patent claim unique elements subject patent proceedings court rejected general_electric attempt patent patent granted william


synthetic element symbol atomic number seventh element discovered component debris hydrogen bomb explosion named albert common half life days produced artificially decay dedicated high power nuclear total yield order year synthesis followed complex process separating products decay synthesized laboratories smaller amounts bombarding heavy elements light owing small amounts produced short half life easily produced currently practical applications outside basic scientific research particular time new element soft metal chemistry typical late state state accessible especially high produces visible glow rapidly damages metal released heat difficulty studying properties conversion rate day longest half life half life days suitable investigation physical properties proven far difficult produce available minute quantities bulk element highest atomic number observed quantities pure form common short lived like synthetic elements radioactive considered highly dangerous health history identified december albert workers university california berkeley collaboration los national laboratories fallout ivy mike nuclear test test carried november pacific_ocean successful test hydrogen bomb initial examination debris explosion shown production new formed absorption nucleus followed beta formula time multiple absorption thought extremely rare process identification indicated captured producing new elements heavier workers analyzed filter papers flown explosion cloud sampling technique discover larger amounts radioactive material later isolated coral debris delivered separation suspected new elements carried presence acid solution weakly acidic medium exchange elevated temperatures fewer recovered end element detected characteristic high energy alpha decay produced capture followed seven beta half life days multiple absorption possible high density newly generated heavy plenty available absorb lighter elements capture initially raised mass number changing atomic number beta resulted gradual increase atomic number formula absorb total resulting new element discovery new elements associated new data multiple capture initially kept secret orders military cold war tensions competition soviet_union nuclear technologies rapid capture provide needed direct experimental confirmation called process multiple absorption needed explain cosmic production certain heavy chemical elements heavier explosions beta decay process needed explain existence stable elements universe element new element produced berkeley laboratories nuclear reaction later intense formula results published articles studies carried elements berkeley team reported results chemical properties ivy mike results published discovery elements american teams competed group nobel institute physics stockholm sweden late early swedish group succeeded synthesis light element particular bombarding oxygen results published priority berkeley team generally recognized publications preceded swedish article based previously undisclosed results explosion berkeley team given privilege new elements effort led design ivy mike project element jokingly nicknamed official names suggested berkeley group derived prominent scientists albert suggest element atomic number symbol albert element atomic number symbol died names announced discovery new elements announced albert geneva atomic conference held august symbol given later changed characteristics physical synthetic white radioactive metal periodic table located right left shares similarities physical chemical properties density lower nearly despite atomic heavier melting point relatively low soft metal bulk value lowest non metals contrary lighter double structure ambient conditions believed face centered cubic symmetry space group constant report room temperature metal converted phase heating self damage induced strong rapidly destroys crystal energy release process visible glow processes contribute relatively low density melting point owing small size available samples melting point observing sample heated inside electron microscope surface effects small samples reduce melting point value metal noticeably high order reduce self radiation damage measurements solid compounds performed right thermal compounds studied atmosphere gas example sample partly apart self destruction solid compounds difficulties studying element include common available twice year sub amounts self contamination rapid conversion rate day formula samples contaminated properties experimental data accumulated time experimental techniques contamination problem include selective optical laser studying properties magnetic properties studied metal materials showed behavior liquid room temperature effective magnetic moments highest values corresponding temperatures chemical like state stable solution induced pale pink color existence firmly established especially solid phase state observed including compounds obtained example reducing iii state studies uncertain nineteen nuclear known atomic weights ranging radioactive stable half life days stable half life days days days remaining half lives shorter hours decay minutes nuclear stable half life hours nuclear high rate nuclear results low critical mass sustained nuclear chain reaction mass kilograms bare sphere lowered adding centimeter thick steel kilograms thick water small critical mass greatly exceeds total isolated far especially rare natural occurrence short half life possibly present earth formation decayed synthesis naturally occurring earth crust requires multiple capture extremely unlikely event produced earth scientific laboratories high power nuclear nuclear weapons tests present years time synthesis elements including occurred naturally natural nuclear longer observed star synthesis extraction produced minute quantities bombarding lighter dedicated high nuclear world major sources high oak ridge national laboratory tennessee loop research institute atomic russia dedicated production elements facilities similar power levels expected comparable production capacities elements quantities produced widely reported typical processing campaign oak ridge tens grams produce quantities quantities quantities microscopic sample sample weighing prepared special magnetic balance designed estimate weight larger produced later starting kilograms yields followed steady production year quantities refer integral target right subsequent separation procedures reduced pure roughly laboratory synthesis heavy results major half life days spontaneous half life years half life hours half life days half life days alternative route involves bombardment high intensity nitrogen oxygen beams half life minutes produced carbon nitrogen reaction realized russia involved scientists awarded prize produced mainly half life minutes releases particles energy ratio particles formula heavier obtained bombarding particles liberated process making possible formation different reaction formula produced target thermal hours formula synthesis nuclear explosions analysis debris ivy mike nuclear test long term project goals studying efficiency production elements high power nuclear explosions motivation experiments synthesis elements requires multiple capture probability events increases nuclear explosions powerful man sources providing order cm2 cm2 comparison cm2 dedicated laboratory set right preliminary analysis debris decayed time debris samples reached mainland laboratory receiving samples analysis soon possible equipped paper filters flew tests hoped discover new chemical elements heavier found series explosions conducted atmospheric results supplemented underground test data accumulated 1960s nevada test site hoped powerful explosions conducted confined space result improved yields heavier apart traditional charges combinations tried mixed charge successful terms yield attributed stronger losses heavy enhanced rates heavy element charges product isolation problematic explosions spreading debris melting surrounding rocks depths meters drilling depths extract products slow inefficient terms collected volumes underground tests carried powerful highest yield elements normally year high power produced major practical problem entire proposal collecting radioactive debris dispersed powerful blast aircraft filters total collection tons increased fraction orders magnitude extraction kilograms underground rocks days explosion recovered total charge elements batch times higher rock picked days test demonstrated highly non linear dependence elements yield retrieved radioactive rock shafts site test order accelerate sample collection explosion explosion expel radioactive material shafts collecting volumes near surface method tried tests instantly provided hundreds kilograms material concentration times lower samples obtained drilling method efficient scientific studies short lived improve overall collection efficiency produced new elements apart detected nuclear test debris total yields elements low tests provide significantly higher amounts rare heavy previously available laboratories separation separation procedure depends synthesis method case light bombardment inside heavy target attached thin foil generated simply washed foil produced amounts experiments relatively low yields higher product mixture produced nuclear case isolation tedious procedure involves repeating steps exchange elevated temperature pressure separation important common produced nuclear half life days fast experiments separation relies fact easily solid state including remain state solutions separation products exchange column water solution saturated acid usually followed exchange exchange column exchange column treated separate containing elements elements identified simply based position time solution example separation achieved extraction acid abbreviated stationary organic phase acid mobile phase sequence reversed exchange column separated method advantage free organic agent compared separation column preparation metal highly strong reducing agents required obtain pure metal compounds achieved reduction iii metallic owing low melting point high rate self radiation damage high pressure higher makes reduction reaction inefficient tried early preparation attempts quickly abandoned favor reduction iii metal chemical compounds iii obtained burning iii forms cubic crystals characterized samples sized phases known formation certain phase depends preparation technique sample history clear phase phases occur spontaneously result self self heating phase iii surrounded coordinated group known states stable state iii precipitated iii solutions reaction alternative preparation procedure exposure iii gas pressure temperature crystal structure iii fold coordinated arrangement iii prepared iii atmosphere dry hydrogen minutes cooling orange solid structure type fold coordinated geometry iii pale yellow solid structure type coordinated coordination number compounds obtained reducing hydrogen produced characterized optical absorption structural information available known include synthesized treating mixture water corresponding hydrogen example obtain compounds high potential use radiation therapy complexes synthesized order deliver appropriate organ body experiments performed compounds dogs iii incorporated beta complexes analogous complexes previously showed strongest excited compounds preparing complexes times allowed reducing radiation damage compounds period minutes required measurements resulting weak detected explained unfavorable relative energies individual constituents compound hindered efficient energy transfer matrix similar conclusion drawn observed acid solutions organic solution acid shows broad peak half width excited green light lifetime quantum yield relatively high compared non decay rates associated stronger interaction inner applications use outside basic scientific research aiming production higher elements synthesized target consisting inch berkeley laboratory resulting reaction yielded new element atomic number rare favored production elements large mass relatively long half life days availability significant amounts target attempted synthesis element bombarding linear berkeley california identified setting upper limit cross section reaction formula marker chemical analysis alpha scattering surface surveyor lunar probe large mass reduced overlap signals marker studied lighter elements lunar surface safety available data originates research animals rats ends blood stream goes bones remains years lungs biological half life years rendered irrelevant short half lives stays indefinitely distribution bone surfaces uniform similar


chemical element symbol atomic number white metal dry moist air considered element 6th period transition metals element series traditionally counted rare independently discovered french scientist austrian baron von american chemist charles james men found mineral previously thought consist entirely dispute priority discovery occurred shortly accusing publishing results influenced published research naming honor went published results earlier chose new element spelling element changed priority finally granted names adopted official ones later element proposed german scientists 1950s particularly abundant element significantly common silver earth crust specific uses relatively abundant radioactive half life billion years determine age usually occurs association element metal catalyst chemical reactions therapy nuclear medicine highest characteristics physical properties arranged configuration entering chemical reaction loses single electron unusual reactions invariably involve shell smallest result highest density melting point properties explained position block gives metal properties heavier transition metals occasionally classified transition metal basis chemical properties compounds compounds contain element state solutions form white drying common exception form water metal slightly unstable air standard conditions burns readily form resulting compound known absorb water carbon dioxide remove compounds closed similar observations reaction water slow cold fast hot formed reaction metal known react form water readily weak acid form solutions containing coordinated seven water molecules average occurs earth form stable making element beta decay half life years makes natural date synthetic element characterized ranging mass stable half life years half life years remaining radioactive half lives days majority half lives half hour lighter stable decay electron capture produce alpha heavier decay primarily beta decay producing element nuclear masses mass number corresponds stable half life days half life days longer half lives ground states radioactive history derived latin paris independently discovered french scientist austrian baron von american chemist charles james found thought swiss chemist jean charles consist entirely scientists proposed different names elements chose chose articles accused man publishing results based author international commission atomic weights responsible new element names settled dispute granting priority adopting names official ones based fact separation described names recognized reverted 1950s german speaking called spelling element changed samples pure samples contained traces later thinking discovered element named actually pure charles james stayed priority argument worked larger scale possessed largest supply time pure metal produced occurrence production found rare earth metals difficult separate elements principal commercially viable ore rare earth mineral etc contains element abundance earth crust main mining areas china united_states brazil india sri_lanka australia world production form tonnes year pure metal difficult prepare expensive rare earth metals price kilogram fourth gold crushed minerals treated hot concentrated acid produce water rare solution removed solution treated convert rare converted dissolved acid main components rare earth metals including separated double salt separated exchange process rare earth suitable exchange exchange hydrogen present washed suitable agent metal obtained reduction metal earth metal applications rarity high price commercial uses stable petroleum cracking applications aluminium proposed use lens material high index additionally tiny added magnetic bubble memory devices currently preferred compound pet led light aside stable radioactive specific uses suitable half life decay mode pure beta exposed activation dating date synthetic bound targeted therapy seeing increasing use therapy bone pain known stable white material density ideal host ray white material dioxide density contains radioactive precautions like rare earth metals regarded having low degree compounds handled care nonetheless example dangerous compound skin dangerous explode burn heated powder toxic similarly group elements known biological role found humans concentrating bones lesser extent liver known occur nature element abundant human body human monitored content known average human takes year coming tiny amounts taken plants mildly toxic ones


chemical element symbol atomic number properties intermediate elements periodic table rarely occurs state pure ore compounds earth crust greek meaning moon discovered jacob noted similarity new element previously discovered named earth found metal partially replaces commercially produced production minerals pure compounds known rare chief commercial uses today applications electronics important supplanted devices types power surge type quantum dot toxic large amounts trace amounts necessary cellular function organisms including animals ingredient including infant formula component indirectly reduce certain molecules animals plants found convert requirements plants differ species plants requiring relatively large amounts apparently requiring characteristics physical properties forms temperature changes depending somewhat rate temperature change prepared chemical reactions usually brick red powder rapidly melted forms black form usually sold commercially structure black irregular complex consists rings ring black solid slightly heating converts gray transformation temperature reduced presence red forms produced solutions black varying rate usually relatively low crystal contain nearly identical rings different arrangements packing dense form rings distance angle contain rings stable dense form gray crystal consisting chains distance angle minimum distance chains gray formed mild heating slow cooling melting point forms gray showing unlike air attacked strong reducing agents forms exhibit changes undergoes gradually heated naturally occurring synthetic identified stable practical purposes recent changes measured half life important dose calculations geological disposal long lived radioactive waste chemical compounds compounds commonly exist states compounds forms dioxide dioxide formed reaction oxygen solid forms molecules gas phase water form acid acid directly acid unlike forms stable unstable dioxide produced laboratory reaction potassium acid called include silver hydrogen acid produce consists rings approximate composition individual rings varying composition agent chemistry glass reducing agent fireworks synthesized acid produced dioxide hydrogen hot concentrated acid react gold form gold iii compounds known stable better known corresponding known species structurally analogous corresponding important reagent preparation compounds preparation prepared treating form comparison counterpart toxic specialty analogous behavior forms hydrogen strongly toxic gas acidic solution forms variety compounds including minerals obtained commercially include mercury lead copper materials highly metals aluminium prone metal react form exist chains compounds explosive orange compound analogous synthesized reaction yield compounds especially state forms stable bonds carbon structurally analogous corresponding compounds especially common representatives include respectively chemistry represented chemistry formula organic synthesis illustrated elimination reaction consistent trends indicated double bond rule rarely observed history greek meaning moon discovered owned chemistry plant near sweden producing acid lead chamber process created red lead chambers presumed compound use acid discontinued wanted use observed red gave smell like burned smell typical similar odor known compounds letter alexander stated compound lack compounds minerals eventually led red wrote second letter describing newly found element similar similarity named earth named new element moon smith found electrical resistance grey dependent ambient light led use cell sensing light commercial products developed cell developed alexander graham bell electric current proportional light falling surface phenomenon design light meters similar devices properties found numerous applications electronics development began early 1930s replaced copper efficient lasted commercial applications 1970s following replaced expensive efficient came medical notice later human beings working industries recognized important seen animals eaten high plants hints specific biological functions discovered discovered essential life 1970s shown present independent sets followed discovery proteins 1980s shown mechanism worked bacteria mammals element occurrence native rare mineral usually form good crystals steep tiny hair like crystals isolation complicated presence compounds elements occurs naturally number forms including minerals rare common mineral mineral contains type calcium named like moon discovery commonly found replacing small metals living systems found compounds plays role analogous naturally occurring compound certain rich plants soils occurs forms analogous rivers easily runoff ocean water contains significant amounts sources include coal burning mining production commonly produced copper lead metal particularly productive obtained mud copper source mud lead chambers acid plants process longer refined number methods comes copper producing acid invention extraction production copper produces increasing share worldwide copper supply changes availability small ore copper industrial production usually involves extraction dioxide obtained copper common production begins produce dioxide mixed water form acid step acid dioxide reduction step tonnes produced worldwide germany japan belgium russia total reserves estimated tonnes data exclude major producers united_states china previous sharp increase observed price relatively stable pound pound lots increased consumption divided follows glass manufacturing agriculture chemicals electronics china dominant consumer tonnes year applications electro winning addition dioxide decreases power necessary operate cells china largest consumer dioxide purpose average glass production largest commercial use accounting consumption production glass compounds red color glass color green yellow arise iron typical glass purpose added applications red color desired produced cds replace toxic lead regulation lead drinking water applications safe drinking water act reduction lead brass necessary new brass marketed like lead improves steel concentrations produces improvement copper solar cells copper material solar cells uses small amounts compounds modify production rubber demand electronics industry declining despite number continuing applications properties useful light meters solar cells use plain paper leading application 1980s application declined large end use switched organic widely replaced replaced based devices notable exception power surge protection superior energy capabilities desirable metal material blue dominating market important component quantum dots sheets convert ray images patterns charge solid state flat panel ray cameras catalyst chemical reactions widely issues ray incorporation place helps multiple single photographic prints sold numerous photographic manufacturers extends range black white photographic images improves prints gamma source industrial biological role toxic large essential animals plants occurs mineral toxic proportions forage plants accumulate defense eaten animals plants require growth indicates presence soil plant nutrition component unusual humans trace element nutrient functions reduction certain forms found animals plants occurs living organisms forms plants require family certain reactions remove oxygen species hydrogen organic cell uses use known types activate subfamily use rare acid works breakdown products use disease body cells attacked alien reduction reported intake increased reduces effects mercury effective low modest mercury evidence suggests molecular mechanisms mercury includes required prevent reverse damage brain tissues evolution biology billion years ago families drive evolution acid incorporated families bacteria protect cells damage families cells phylogenetic origin containing form occurs species diverse green algae sea fish chicken involved small reducing molecules family bearing molecules destroys repairs damaged cell membranes bearing plants animals generates reduced serves electron source important reducing makes dna trace elements involved activities copper lacking terrestrial mineral areas marine organisms retained expanded terrestrial organisms reduced completely lost findings suggest exception aquatic life supports use terrestrial habitats lead reduced use trace element marine fishes highest concentration million years ago freshwater terrestrial plants slowly production new acid including etc appeared recently million years fruits flowers plants fact dominant type plant today evolved late period constitute family identified function able extract involved regulation participating protection damage produced million years ago new developed sources comes nuts mushrooms brazil nuts richest source soil dependent brazil require high levels element needs recommended day supplement available forms including multi mineral typically day specific day june food drug administration published final rule establishing requirement minimum maximum levels infant formula content human body believed range indicator plant species certain species plants considered high content soil require high levels thrive main indicator plants species including prince woody false medical use substance loosely called approximate formula active ingredient anti compound kills fungus causes dry skin fragments ingredient body treat infection different species fungus detection biological measured blood monitor excessive environmental exposure confirm diagnosis poisoning hospitalized victims investigate suspected case fatal techniques capable distinguishing organic forms element organic forms largely converted body prior elimination cancer patients receiving daily oral achieve high concentrations essential trace element toxic taken excess exceeding upper intake level day lead upper intake level based primarily study chinese patients exhibited overt signs follow study people study actually found maximum safe intake approximately day kilogram body weight suggested day avoid creating nutrients diet accord data countries china people corn grown extremely rich coal suffered coal shown content high highest concentration coal recorded signs symptoms include odor breath disorders hair loss nails fatigue damage extreme cases exhibit liver death metallic relatively low low contrast mode action similar toxic chronic toxic dose humans day hydrogen extremely toxic gas occurs organic compounds high toxic large april polo died shortly match united_states polo open days later released statement explaining horses received incorrect dose ingredients mineral supplement compound incorrectly compounded analysis blood levels compounds supplement indicated concentrations times higher normal blood samples times higher normal liver samples later confirmed toxic factor poisoning water systems result new agricultural runoff courses normally dry undeveloped lands process natural compounds water concentrated new wetlands water pollution waterways occurs coal ash mining metal crude oil processing resultant high levels waterways found cause disorders species including wetland birds fish elevated levels harm species fish wildlife necessary life toxic high salmon optimal concentration body weight level young salmon die die toxic excess safety health administration set legal limit exposure limit workplace hour national institute safety health set recommended exposure limit hour levels immediately dangerous life health rare healthy individuals occur patients severely compromised function undergoing total nutrition advanced age people dependent food grown soil risk new_zealand soil low levels adverse health effects detected residents defined low normal activity levels brain tissues occurs low level linked additional stress high mercury increased stress nutrients effect health remains uncertain particularly relation disease minerals copper high pregnant animals ratio lead reduction treatment cases levels monitored studies needed interactions regions regions north_america low soil levels lead low concentrations plants animal species supplemented diet injection particularly susceptible general absorption lower animals lower grain grazing certain white varieties containing higher requirements presumably released activity acting risk white muscle disease administered injection respond controversial health effects number studies implicated measured blood levels number chronic diseases cancer diabetes hiv aids tuberculosis addition found types cancer types blinded controlled prospective trials humans succeeded reducing disease analysis studies detected decrease overall mortality


originally chemical element symbol atomic number radioactive elements followed periodic table elements stable forms distinction shared forms combined elements shows stable state compounds exist suggested element properties intermediate known elements confirmed henry having measured atomic numbers elements known found element atomic number italian american group claimed isolated sample element discoveries soon proven false nuclear experiment conducted ohio_state university radioactive produced certainly lack chemical proof element produced discovery generally recognized produced characterized oak ridge national laboratory separation analysis products fuel proposed spelling subsequently changed derived greek mythology stole fire mount brought humans symbolize daring possible mankind intellect sample metal possible sources natural rare natural producing practical applications exist chemical compounds paint atomic batteries thickness measurement devices stable natural scarce typically synthesized bombarding enriched thermal produce properties physical properties arranged configuration forming compounds loses belongs open element atomic radius largest slightly greater neighboring elements exception general trend increase atomic radius caused caused filled half filled properties rely position intermediate example melting point energies energy greater lower similarly estimate boiling point radius standard heat formation gas greater double close packed structure low temperature alpha form converts beta body centered cubic phase heating chemical properties compounds belongs group similar neighboring elements instability chemical studies incomplete compounds synthesized fully studied general tend pink red color treatment acidic solutions containing results gelatinous light brown sediment water dissolved acid water yellow salt produced similarly dissolved acid results dried forms pink crystals similar electron configuration color pink ground state term symbol slightly like group cell parameters calculated lead conclusion density lowest unlike similar corresponding salt salt synthesized heating white colored powder structure powder cubic heating transforms phases respectively phases adjusting time temperature forms stable state form line according position periodic table element expected form stable states treating chemical compounds containing strong reducing agents showed easily reduced elements stable long lived result rarely occurring effect liquid drop model neighbor element stable element primary decay products lighter generally decay electron capture heavier beta decay nuclear decay rare alpha decay mode stable element specific activity half life years electron capture magic number corresponds stable configuration alpha particle form observed alpha decay partial half life alpha decay years relative probability nucleus decay way etc positive energy release alpha decay alpha predicted occur observed element nuclear mass numbers mass numbers stable half life days longer half lives ground states note longer half life ground state occurrence found weak beta activity pure attributed half life years years later claimed element occurs natural quantities grams observations newer investigations seven naturally occurring single beta produce forbidden energy conservation particular careful measurements atomic masses mass difference negative absolutely prevents single beta decay natural larger mass sums potential alpha daughters plus alpha particle stable practice alpha decay research del showed half life years shown responsible grams earth crust alpha found theoretically calculated half life high low energy decay process probably observed finally formed nature product spontaneous trace amounts found naturally occurring sample found contain concentration parts mass responsible earth crust identified spectrum star found star short half life formed near surface stars history searches element czech chemist found difference largest neighboring pairs conclusion suggested element intermediate properties prediction supported henry having discovered atomic number property elements found atomic numbers element correspond gaps knowledge gap periodic table groups started search predicted element rare natural environment claim discovery published florence italy separating mixture rare earth elements concentrate brazilian mineral yielded solution containing solution gave ray attributed element honor city named element results published scientists claimed experiments group scientists university illinois smith published discovery element named university reported discoveries shown erroneous spectrum line corresponded element identical lines thought belong element turned belong platinum finally formulated rule indirect consequences rule element unable form stable nuclear experiment conducted law ohio_state university produced certainly proposed lack chemical proof element produced discovery largely recognized discovery synthesis metal produced characterized oak ridge national laboratory clinton laboratories time jacob lawrence charles separation analysis products fuel busy military related research world war announce discovery original proposed laboratory work conducted suggested grace mary wife derived greek mythology stole fire mount brought humans daring possible mankind intellect spelling changed closer accordance metals iii metal located outer contained metal times excess compared creating vacuum chemicals mixed produce metal sample produced measure metal properties melting point exchange methods prepare grams nuclear fuel processing today recovered produced bombarding turning beta decay half life days production production methods different vary given industrial applications produced large quantities compared bombarding thermal output relatively high total product way produce short half life obtained bombarding enriched thermal bombarding target energetic particle method bombard fast cause fast multiple reaction products creates early 1960s oak ridge national laboratory produce grams year world large volume synthesis facility scale production discontinued early 1980s possibly resumed high currently russia country producing relatively large scale applications research purposes found outside laboratories obtained quantities gamma rays radiation relatively small penetration depth matter relatively long half life signal lights use paint containing beta radiation emitted light cause aging alpha light stable years originally purpose later replaced favored safety reasons atomic batteries beta particles emitted converted electric current small source plates batteries useful lifetime years based battery assembled generated power volume cubic inches including measure thickness materials evaluating radiation source passes sample possible future uses portable ray sources auxiliary heat power sources space satellites alpha standard space exploration related uses precautions element like biological role rays beta decay dangerous interactions tiny quantities hazardous certain precautions observed general gloves covers safety glasses outer layer easily removed protective clothing known human organs affected interaction possible candidate bone tissues sealed dangerous packaging damaged dangerous environment humans radioactive contamination found contaminated area washed water soap mainly affects skin skin leak found area identified hazardous evacuated emergency services contacted dangers aside known


chemical element symbol atomic number named honor physicist synthetic element element created laboratory found nature radioactive stable known half life approximately hours periodic table elements block element second fourth row transition elements member 7th period belongs group elements chemistry experiments confirmed heavier group chemical properties characterized partly compare chemistry group elements calculations indicated element significantly different properties effects 1960s small amounts produced laboratories soviet_union california priority discovery naming element disputed soviet american scientists international union pure applied chemistry established official element history discovery reportedly detected joint institute nuclear research soviet_union researchers bombarded target separated reaction products gradient conversion interaction team identified spontaneous activity contained volatile portraying properties half life accurately determined later calculations indicated product likely abbreviated standard researchers university california berkeley synthesized element bombarding target measured alpha decay daughter decay american synthesis independently confirmed secured identification parent observation alpha rays signature decay product naming controversy russian scientists proposed american scientists suggested new element working group assessed claims discovery concluded teams provided contemporaneous evidence synthesis element credit shared groups american group wrote scathing response findings stating given emphasis results group particular pointed russian group altered details claims times period years fact russian team deny stressed given chemistry experiments performed russians accused having appropriately qualified personnel committee responded saying case having assessed point raised american group said found reason alter conclusion priority discovery finally suggested american team way reflect change opinion consequence initial competing claims discovery element naming controversy arose soviets claimed detected new element suggested honor head soviet nuclear research books soviet official element americans proposed new element honor known father nuclear physics international union pure applied chemistry adopted temporary systematic element derived latin names suggested suggested element felt team recognized contributions dispute names elements teams involved resolved dispute adopted current given element time stable naturally occurring radioactive synthesized laboratory observing decay heavier elements sixteen different reported atomic masses exceptions decay predominantly spontaneous pathways life times half lives known lighter usually shorter half lives half lives observed stable live seconds stable min respectively heaviest stable having measured half life half lives higher known synthesized direct fusion lighter decay products heaviest produced direct fusion heavier observed decay products elements larger atomic numbers confirmed heavy observed electron capture daughters short half lives spontaneous likely true likely daughter observed predicted long half life discovery predicted longer half life half life min american scientists university california berkeley announced succeeded parent reported emitted seven alpha particles form claim retracted predicted properties chemical element member series transition metals calculations atomic radius energies ground levels states similar different lead concluded basic properties resemble group elements properties determined gas phase experiments chemistry state stable state elements exhibit stable state addition expected able form stable state chemical properties based calculation indicated effects electron shell strong lower energy level giving electron configuration making element behave like lead better calculation methods studies chemical properties compounds shown according rest group elements analogous manner projected form stable high melting point form contact water form volatile existing molecules phase phase similar extent resulting treatment promotes formation complex use produces complexes complexes tend form complexes larger complexes possible physical atomic expected solid normal conditions assume close packed crystal structure similar lighter heavy metal density comparison known element density measured density results high atomic weight effects production measure quantity impractical sample quickly decay atomic radius expected predicted instead opposite behavior lighter experimental chemistry gas phase early work study chemistry focused gas measurement relative deposition temperature curves initial work carried attempt discovery element recent work reliable identification parent studies experiments relied expectation begin new series elements form volatile nature volatile lighter bonds series experiments confirmed typical member group forming decreased observed potassium provided solid phase instead gas highly indicative formation mixed salt phase expected electron configuration behave heavier group periodic table readily form strong acid solution readily form complexes acid acid solutions conclusive chemistry studies performed japanese team japan atomic energy research institute extraction experiments acid solutions proved non behavior comparison lighter placed firmly group indicated formation complex solutions manner similar similar results observed acid solutions differences extraction curves interpreted weaker affinity formation complex seven concentrations


chemical element symbol atomic number extremely radioactive synthetic element created laboratory stable known half life approximately seconds possible nuclear longer half life min created centre heavy research near germany named periodic table elements block element reactions gold shown extremely volatile metal group element gas standard temperature pressure calculated properties differ lighter mercury notable withdrawing ones effects confirm undisputed transition metal calculated state mercury shows compound extreme conditions predicted difficult neutral state group elements total approximately detected nuclear reactions history official discovery created february germany victor element created firing accelerated target heavy single second subsequently dismissed produced mass number successfully repeated experiment reaction repeated search super heavy element gas filled set confirm decay data reported team joint working party assessed claim discovery team cases found insufficient evidence support claim primarily related decay data known team studied reaction able confirm decay data found existing data designated reported claims discovery element officially recognized team element decision based confirmation decay properties daughter experiments naming nomenclature unnamed elements known mercury published recommendations according element called corresponding symbol systematic element element discovered discovery confirmed permanent decided widely chemical community levels chemistry classrooms advanced textbooks recommendations ignored scientists field called element symbol simply acknowledging team discovery asked suggest permanent element july proposed element symbol honor outstanding scientist changed view world standard month discussion period scientific community naming pointed symbol previously associated known reason use future symbol prompting team forward symbol alternative february anniversary birth officially accepted proposed symbol stable naturally occurring radioactive synthesized laboratory observing decay heavier elements different reported atomic masses known states decay predominantly alpha decay undergo spontaneous instrumental confirmation discoveries elements half lives extremely unstable radioactive general heavier stable lighter stable half life seconds suspected half life minutes half life minutes half lives shorter seconds half lives half lives slightly predicted heavy half lives years produced process cosmic rays times abundant lead synthesized direct fusion lighter decay products known decay product heavier known produced decay heavier heaviest produced direct fusion heavier observed decay products elements larger atomic numbers american scientists university california berkeley announced succeeded parent reported emitted alpha particles form claimed undergone alpha decay alpha particle decay energy half life claim retracted produced team new data contradicted previous fabricated data predicted properties chemical member series transition metals heaviest group element periodic table mercury predicted differ significantly lighter group elements electronic ones caused effects likely electronic configuration unlike fact participate readily chemical bonding mean behave like transition metal lighter especially state water solutions likely form states stable lighter group members state common mercury state highly uncommon existing compound mercury extreme conditions analogous compound predicted stable featuring mercury state known predicted unstable non existent neutral state likely difficult previous group members unstable analogous mercury compound mercury spontaneously constituent elements polar predicted form analogous neutral respectively analogous stable solution able exist solution group elements period elements expected contracted strongly closed shell configuration result probably noble metal metallic bonds weak possibly making extremely volatile like noble gases potentially making room temperature able form metal metal bonds copper platinum silver gold bonds predicted weaker analogous bonds mercury physical atomic heavy metal density solid state comparison dense known element density measured density results high atomic weight effects production measure quantity impractical sample quickly decay calculations predict gas room temperature metal periodic table second closed shell electron configurations atomic radius expected predicted instead opposite behavior lighter addition binding expected spin orbit making behave similarly terms size shape energy noble transition metal band gap expected close packed crystal structure parameters ratio ideal value establishing solid solid noble gases cohesive energy order mercury near lower value noble gases experimental atomic gas phase chemistry interest chemistry sparked predictions largest effects period group ground state electron configuration belong group periodic table according principle behave heavier mercury form strong compounds noble metals like gold experiments focused element gold surface held varying temperatures order owing shows like properties experiments performed simultaneous formation mercury allowing comparison characteristics experiments conducted reaction detection spontaneous claimed parent half life minutes analysis data indicated volatile mercury noble gas properties confusion synthesis cast doubt experimental results given uncertainty april psi team conducted experiments synthesis daughter nuclear reaction experiment identified properties indicated volatile mercury formation weak metal metal bond gold placing firmly group april experiment repeated positively identified property confirmed indicated properties completely agreement heaviest member group experiments allowed experimental boiling point


radioactive chemical element symbol atomic number element series named marie known research intentionally produced identified july group university california berkeley discovery kept secret released public november produced bombarding nuclear spent nuclear fuel contains grams hard dense metal relatively high melting point boiling point ambient conditions cooling magnetic transitions observed compounds compounds usually exhibits predominant solutions readily dominant form element forms strongly complexes organic compounds evidence incorporation bacteria introduced human body bones lungs liver promotes cancer known radioactive small critical mass sustained nuclear chain reaction predominantly particles heat released process potentially produce electricity generators application hindered high cost production heavier power sources artificial served source alpha particle ray installed space including spirit opportunity curiosity mars analyze composition structure surface history likely produced previous nuclear experiments intentionally synthesized isolated identified university california berkeley james albert experiments inch identified laboratory national laboratory university_of_chicago element discovered fourth series lighter element unknown time sample prepared follows solution coated platinum foil cm2 area solution converted following coating dissolved acid precipitated concentrated solution dissolved acid separation carried exchange yield certain separation berkeley group initially called elements greek demons hell latin madness produced july august bombarding particles produce release formula identified characteristic energy particles emitted decay formula half life alpha decay measured days corrected days produced similar reaction march formula half life decay correctly determined days discovery closely related manhattan_project results confidential leaked synthesis elements radio children kids days official presentation american chemical society meeting november listeners asked new element discovered war discovery production compounds later patented listing inventor new element named marie husband noted discovering work followed example element periodic table named explorer rare earth elements element atomic number like propose symbol evidence indicates element contains seven analogous element seven regular rare earth series base element named manner analogous naming chemist honored samples barely visible identified louis created substantial sample university california bombarding amounts iii obtained crane magnetic close providing experimental evidence compounds metal produced reduction characteristics physical synthetic radioactive element hard dense metal white appearance physical chemical properties resembling melting point significantly higher previous elements comparison boiling point density significantly lighter heavier metals forms stable ambient conditions symmetry space group parameters formula units unit cell crystal consists double close packing layer sequence pressures room temperature transforms face centered cubic symmetry space group constant compression transforms structure similar transitions observed phases referred iii peculiar magnetic properties neighbor element shows entire temperature range transforms state cooling exhibits transition transitions cooling similarly magnetic transitions cooling transition character somewhat different ordering accordance magnetic data electrical increases temperature twice remains nearly constant room temperature significant increase time self damage crystal alpha radiation makes uncertain absolute value similar significantly higher illumination iii exhibit strong stable yellow orange maximum range depending environment originates transitions excited state ground state analysis allows monitoring interactions iii organic complexes chemical solution exclusively assume state stable state state observed mainly solid phases known presence strong potassium easily reduced iii water chemical behavior different similar solution pale green pale yellow optical absorption contains sharp peaks strength directly converted concentration state reported solution prepared beta decay failure obtain iii high potential instability hard lewis form stable complexes hard bases bonding small component complexes commonly exhibits fold coordination environment geometry nuclear known stable longest half lives reported million years years long lived half life years years years unusual predominantly spontaneous commonly half lives days years respectively undergo self sustaining nuclear chain reaction principle act nuclear fuel elements nuclear cross section especially high odd mass thermal mixture suitable fast mass thermal accumulate burn increases mixed fuel power contain little activation create strong end fuel cycle increase dose personnel minor fuel thermal excluded fuel placed special fuel rods present table right lists critical masses sphere metal steel critical masses odd water thickness critical mass small significant uncertainty critical mass values usually order values listed large respectively research groups currently nuclear fuel owing low availability high price small critical mass portable nuclear weapons reported far suitable purpose short half life strong result excessive heat highly suitable having half life times occurrence longest lived half life million years present earth formation decayed produced artificially small quantities research purposes furthermore occurs spent nuclear fuel present nature certain areas atmospheric nuclear weapons tests conducted analysis debris testing site hydrogen bomb ivy mike november revealed particular smaller quantities reasons military secrecy result published atmospheric compounds poorly common adhere soil particles soil analysis revealed times higher concentration sandy soil particles water present soil pores higher ratio measured soils elements including occurred naturally natural nuclear longer minute amounts produced naturally theoretically predicted extremely rare double beta decay trace observed synthesis preparation produced small quantities nuclear kilograms accumulated grams heavier explains high price quoted usd recent estimate usd usd nuclear formed series nuclear reactions chain captures converts decay transforms capture followed produces converts research purposes obtained available large amounts spent nuclear fuel higher results different reaction chain formation alpha particle resulting small heavier popular scientific research long half lives production rate thermal relatively low prone undergo induced thermal synthesis absorption unlikely short half life intermediate product min converts decay cascade reactions produces mixture different post synthesis separation selective synthesis desired favored research purposes long half life efficient preparation method decay available relatively large quantities long half life years produced method year associated reaction produces purity interesting research obtained decay produced minute quantities metal preparation synthesis routines yield mixture different certain needs separated example procedure dissolve spent fuel fuel acid remove bulk extraction type extraction remaining separated based extraction stripping mixture compound extracted multi step techniques appropriate reagent complex recently proposed reagent highly selective separation similar achieved treating elevated temperature present solutions state complexes remains unchanged isolated repeated metallic obtained reduction compounds initially iii purpose reaction conducted environment free water oxygen apparatus reducing agents formula possibility reduction melt compounds reactions readily oxygen forming known black obtained burning cm2 pure oxygen heating vacuum transforms whitish formula alternatively obtained reducing molecular hydrogen formula furthermore number type known stands metal thermal trace quantities reported produce volatile form volatile known examples rare state observed species reported behave similarly tentatively characterized extremely rare state new experiments indicate exist iii produced introducing iii solutions brown hand obtained reacting iii molecular formula series known form stands metal iii produced reaction iii hydrogen gas converted iii light green iii reacting salt corresponding elevated temperature formula alternative procedure heating corresponding acid phase iii results formula obtained treating vacuum elevated temperature type known elements nitrogen prepared reacting iii metallic elements elevated temperatures compounds biological aspects complexes analogous known molecular theory stable complex reported formation complexes type stands solutions containing confirmed type complexes interact useful selective separation dissolved organic compounds acid compounds related biological activity resulting complexes exhibit strong yellow orange light convenient detection studying interactions changes half life order spectrum biological significance reports bacteria evidence incorporation applications radioactive elements common strong alpha energy relatively short half lives days years produce thermal energy respectively common form generators like spacecraft application studied abandoned price usd year half life good energy yield suitable fuel produces significant amounts harmful gamma beta radiation radioactive decay products requires thinner radiation protection high spontaneous rate gamma radiation rate relatively strong compared competing generator time greater higher gamma requires shield times thicker inches lead source compared application currently considered impractical promising application produce suitable generators cardiac alternative routes use reaction bombardment produce product strong gamma common starting material production higher elements bombardment oxygen yielded certain discovered sized target alpha particles inch berkeley produced experiment ray practical application limited total volume particle source alpha particle ray instruments installed mars mars mars exploration mars science laboratory analyze composition structure rocks surface planet mars surveyor moon source elaborated setup equipped head containing sources having total radioactive decay rate tens roughly sources sample energy alpha particles scattered sample analyzed analysis implemented contain information major elements samples hydrogen safety owing high compounds handled appropriate laboratories special arrangements particles absorbed thin layers common materials decay products significant beta gamma radiation require elaborate protection consumed days absorbed blood goes liver bones remaining bone inside bone significantly time radiation destroys bone stops red blood cell creation biological half life years liver years bones absorbed body strongly allowed total dose form injection containing solutions rats increased bone promoted liver cancer inevitably present spent nuclear fuel concentration decay times thousands years need removed fuel disposal associated procedure involves steps separated converted bombardment special short lived procedure nuclear documented elements developed


chemical element symbol atomic number mildly toxic rare silver white related occasionally found native form crystals far common universe earth extreme rarity earth crust comparable platinum partly high atomic number formation volatile caused element lost space gas hot formation planet discovered empire joseph von mineral containing gold martin named new element latin word earth gold minerals notable natural gold compounds commercially significant source normally extracted product copper lead production commercially primary use foremost steel copper improve applications solar panels material consume considerable fraction production biological function fungi incorporate place humans partly gas like odor breath victims exposure characteristics physical properties white pure state metallic easily black brown powder prepared solution acid acid shows greater electrical certain directions depends atomic alignment increases slightly exposed light state copper iron steel highest melting boiling points respectively chemical properties adopts structure consisting chains gray material air naturally occurring stable observed radioactive stable naturally occurring possibly long half lives unstable range years makes longest half life approximately times age known universe known nuclear atomic masses range elements known undergo alpha decay able undergo mode decay atomic mass exceeds following element occurrence abundance earth crust comparable platinum stable solid elements earth crust abundance comparison abundance chemical elements extreme rarity earth crust reflection cosmic abundance fact greater thousand times abundant earth crust low abundance earth thought conditions earth formation stable form certain elements absence oxygen water controlled power free hydrogen scenario certain elements form volatile severely depleted formation earth crust heavy elements depleted earth crust process found native form found gold different city colorado named hope strike gold gold metal ore found gold usually found found naturally chemical compound combined found gold form found combined elements gold common metals natural minerals occur formed near earth surface contrast general able replace minerals large difference radius consequence common minerals contain considerable amounts traces gold rush discarded material got way searched pure gold waste fill years passed realized waste gold recognized led second gold rush included mining streets history latin meaning earth discovered 18th century gold ore mines near today city romania ore known white gold ore german county gold according von containing native joseph von serving austrian chief inspector mines concluded ore contain following year reported erroneous ore contained gold unknown metal similar thorough investigation lasted years consisted tests determined specific gravity mineral noted like odor white smoke passed new metal heated red color metal acid black solution gives water able identify metal gave names properties predicted expected hungarian scientist discovered element independently ore regarded later gave credit named martin earlier isolated mineral 1960s brought growth applications use free steel dominant use production principal source produced copper component blast lead treatment tons copper ore typically yields kilogram pounds produced mainly united_states peru japan canada year british geological survey gives following numbers united_states peru japan canada contain noble metals compounds formula temperatures air metal reduced metals converted mixture water normally present solution formed process separated adding acid converted dioxide stay solution reduction metal reacting dioxide dioxide acid commercial grade usually marketed powder available sticks year end price pound recent years price driven increased demand limited supply reaching high pound despite expected doubling production improved extraction methods united_states department energy supply compounds belongs chemical family oxygen family compounds similar exhibits states state common reduction metal produces state exhibited compounds metals formed heating acid yields hydrogen highly unstable unstable base stable state exhibited obtained pure form known products organic derived characterized square geometry species exist dark brown black forms mixed state structural group occurs number compounds square attested form state state lower forms state known attested including found reported black solid formed heat vacuum dioxide heating doubt cast existence solid phase known phase fragment black solid merely mixture dioxide dioxide formed heating air causing burn blue flame obtained thermal forms reported literature forms found true state mixture exhibits mixed form series including acid acid acid forms acid form containing respectively acid forms containing include consists fused rings treated concentrated acid forms red solutions containing liquid produces square yellow orange include blue black consists fused rings formed reaction exist distorted cubic geometry formed compounds readily form functional group called functional group attributed prefix like species unstable respect loss hydrogen stable applications largest consumer iron copper lead added steel copper makes metals cast iron promoting purposes presence electrically free tends affect spark testing results lead improves strength decreases action acid electronic industry uses solar panels national energy laboratory lab tests material achieved highest solar cell electric power generation massive commercial production solar panels solar recent years significantly increased demand replaced formed solid state ray mercury form mercury infrared sensitive material formed compounds phase growth compound employed preferred precursor achieving low temperature growth processes highest purity compounds industry prepared media layer types optical discs including compact discs digital video discs dvd blu ray discs dioxide create new phase change memory chips developed lead working elements devices lead far infrared uses color strong increase optical addition glass production glass fibers telecommunications glasses widely delay powder electric blasting caps organic employed living radical electron rich possess activity rubber instead rubber produced way shows improved heat resistance identify members genus typically responsible key constituent high performing mixed selective acid surface composition changes reaction conditions presence steam surface catalyst enriched translates acid production biological role known biological function fungi incorporate place organisms shown highly variable tolerance compounds cells reduce causes characteristic dramatic cells reduction accumulation account major effects organisms partly form formed species observed hot springs low concentrations precautions compounds considered mildly toxic need handled care acute poisoning rare poisoning particularly difficult treat agents treatment metal increase reported humans exposed little air foul like odor known breath caused body converting state volatile compound highly like smell pathways known generally assumed resemble extensively studied final products elements similar people exposed workplace breathing skin contact eye contact safety health administration set legal limit exposure limit exposure workplace hour national institute safety health set recommended exposure limit hour levels immediately dangerous life health


greek smell chemical element symbol atomic number hard bluish white transition metal platinum group found trace element platinum naturally occurring element density platinum platinum group metals employed fountain pen electrical contacts applications extreme needed characteristics physical properties blue gray stable element slightly calculations density ray data produce reliable data elements giving value versus hard metal remains high temperatures low bulk extremely high reported rivals diamond moderately high low pressure lowest platinum group metals high melting point fourth highest elements solid difficult machine form work chemical properties forms compounds states ranging common states state notable highest attained chemical element aside encountered uncertain states represented compounds synthesis cluster compounds common compound exhibiting state toxic compound formed exposed air volatile water pale yellow solid strong smell powder characteristic smell forms red reaction base forms powerful agent contrast dioxide black non volatile toxic compounds major applications tissue electron organic synthesis non volatile organic reactions known synthesized lower states stabilized larger known state known complexes represent state general lower states stabilized good donors containing nitrogen higher states stabilized strong donors despite broad range compounds numerous states bulk form ordinary temperatures pressures attack including regia seven naturally occurring stable abundant undergoes alpha decay long half life years practical purposes considered stable alpha decay predicted seven naturally occurring observed presumably long half lives predicted undergo double beta decay observed daughter half life years extensively dating terrestrial rocks dating measure intensity continental time fix minimum ages mantle roots continental decay reason rich minerals rich notable application geology conjunction abundance layer shocked cretaceous boundary marks extinction million years ago history discovered william london england discovery platinum metals platinum group platinum reached europe small silver encountered late 17th century silver mines department colombia discovery metal distinct new element published studied platinum dissolved regia mixture create observed small dark joseph louis thought victor louis observed black obtain material experiments analyzed concluded contain new metal treated powder alternately obtained volatile new believed new metal named greek word winged advantage larger continued research identified previously elements black obtained yellow solution probably reactions red heat able formed named greek meaning smell smell volatile discovery new elements documented letter royal society june early successful process nitrogen reaction nitrogen hydrogen produce giving yield process economically successful time group led bought world supply use catalyst shortly cheaper based iron iron introduced group pilot plants removing need expensive rare obtained primarily processing platinum occurrence abundant stable element earth crust average mass fraction parts continental crust found nature element natural especially rich rich copper deposits platinum group metals occur compounds platinum exchanged small platinum group metals found naturally copper earth crust like found highest concentrations types structure deposits impact deposits reworked structures largest known primary reserves complex south_africa large copper deposits near russia basin canada significant sources smaller reserves found united_states deposits pre people department colombia source platinum group metals second large deposit found mountains russia mined production obtained commercially product copper mining processing copper noble metals silver gold platinum group metals non metallic elements settle cell mud forms starting material extraction order separate metals brought solution methods available depending separation process composition mixture representative methods fusion followed dissolution regia dissolution mixture acid separated platinum gold base metals regia leaving solid separated treatment containing treated producing water volatile separated precipitation dissolved separated platinum group metals extraction organic volatile method similar procedure methods suitable industrial scale production case product reduced hydrogen yielding metal powder treated powder techniques producers united_states geological survey published production amounts united_states consumption date published gives consumption united_states suggest production ton year estimated production applications extreme rarely pure state instead metals utilized high wear applications hard platinum group metals tips fountain instrument electrical contacts resist wear frequent operation tips late rpm early record era circa compared steel needle points tips wore far rapidly competing diamond tips discontinued detection tissue optical electron strong cross links mainly reacting carbon carbon bonds biological membranes place tissue samples simultaneously extremely electron dense greatly image contrast transmission electron studies biological materials carbon materials weak contrast image compound exhibits similar fixing action related compound potassium important chemical synthesis despite poisonous uses conversion double bond barry won nobel prize chemistry expensive use instead yields cheaper chemical reagent austrian chemist von developed introduced commercially years replaced stable metal highest melting point metals light increases life lamps light manufacturer founded german companies combined lamp production facilities derived elements german like effectively hydrogen potential candidate metal battery expensive react potassium common battery high range electromagnetic spectrum example twice gold high desirable space based reduced mirror sizes space limitations coated mirrors flown space missions aboard space shuttle soon clear oxygen low earth orbit abundant significantly deteriorate layer known clinical use appears patients scandinavia involves local administration highly toxic compound lack reports long term effects suggest depends compound administered compounds reported activity indicated promising future compounds drugs precautions finely divided metallic oxygen room temperature forming volatile compounds converted oxygen present makes main source contact environment highly volatile skin readily toxic skin contact airborne low concentrations cause lung congestion skin eye damage hood rapidly reduced relatively compounds vegetable corn oil price usually sold minimum pure powder like precious metals measured weight grams price kilogram depending quantity supplier


chemical element symbol atomic number extremely radioactive synthetic element element found nature created laboratory stable known half life seconds centre heavy research near germany created element named periodic table block element member 7th period placed group elements chemical experiments carried confirm heavier group calculated similar properties lighter history discovery synthesized august german research team led peter institute heavy research team bombarded target accelerated detected single work confirmed years later joint institute nuclear research soviet_union naming nomenclature unnamed elements known wars synthesis published recommendations according element called corresponding symbol systematic element element discovered discovery confirmed permanent decided widely chemical community levels chemistry classrooms advanced textbooks recommendations ignored scientists field called element symbol simply proposed naming discussed element naming controversy names elements proposal disputed suggested honor austrian physicist nuclear recommended officially adopted element named specifically non mythological woman named marie stable naturally occurring radioactive synthesized laboratory observing decay heavier elements different reported atomic masses known unconfirmed states decay predominantly alpha decay undergo spontaneous stability half lives extremely unstable radioactive general heavier stable lighter stable known heaviest known half life seconds nuclear reported half life second half lives seconds respectively remaining half lives predicted stable beta decay known observed undergo beta decay unknown predicted half lives longer known discovery predicted half lives seconds minute respectively later found half lives seconds respectively predicted properties chemical seventh member series transition metals element shown transition metal expected elements form fourth transition metal series platinum group metals calculations atomic similar lighter implying basic properties resemble group elements prediction probable chemical properties received attention recently expected noble metal based stable states lighter group elements stable states predicted states state stable solutions comparison maximum state stable states state represented possible expected stable predicted similar allowing stable state expected maximum states elements element element stable gas phase solution physical atomic expected solid normal conditions assume face centered cubic crystal structure similarly lighter heavy metal density second highest known elements second predicted neighbor comparison known element density measured density results high atomic weight effects production measure quantity impractical sample quickly decay predicted predicted radius larger example bond distance expected atomic radius expected experimental chemistry determination chemical characteristics established short half lives limited number likely volatile compounds studied small scale compounds likely sufficiently volatile lighter volatile analogous compound sufficiently volatile volatile possible chemical studies carried produced half life second rate production week half life stable known seconds long perform chemical studies obstacle need increase rate production allow experiments carry weeks months significant results obtained separation detection carried continuously separate automated systems experiment gas phase solution chemistry yields heavier elements predicted smaller lighter elements separation techniques reused experimental chemistry received attention heavier elements lawrence berkeley national laboratory attempted possible chemical investigation expected stable magic number deformed half life predicted seconds long chemical investigation detected currently unknown experiment determining chemical properties need compare compound analogous compounds lighter example chemical characterization compared analogous compound preliminary step determining chemical properties attempted compounds iii iii amounts presence carbon particles temperatures far high procedures current methods investigation chemistry elements work


soft white metallic chemical element symbol atomic number rapidly exposed air soft cut knife gave series group similar elements periodic table considered element 6th period transition metals traditionally counted rare earth elements assumes state biological role toxic usually occurs rare earth elements found swedish chemist ancient greek meaning lie hidden classified rare earth element 28th abundant element earth crust times abundant lead minerals makes quarter content extracted minerals process complexity pure metal isolated compounds numerous applications glass carbon lighting studio lighting projection elements electron approved medicine treating failure characteristics physical element prototype series periodic table appears right earth metal left considered group element lighter heavier radioactive classification disputed similarly arranged configuration outside noble gas core chemical reactions gives form state achieving stable configuration preceding noble gas compounds known stable exceptional sudden lowering energy important chemistry begins happen weakly unlike strongly later exceptions shell completely furthermore melting points related extent second lowest melting point harder series traversed expected soft metal relatively high room temperature comparison value good conductor aluminium volatile like crystal structure room temperature changes face centered cubic structure changes body centered cubic structure chemical expected periodic trends largest atomic radius stable group elements slowly air burning readily form iii basic calcium centimeter sized sample completely year like iron instead forming protective coating like aluminium lighter room temperature form warming form compounds nitrogen carbon slowly water form iii acid readily forms solution strongest hardest base naturally occurring stable long lived far abundant making natural produced process slow capture occurs medium mass stars process rapid capture occurs core collapse rare odd odd long half life years rich produced processes produced process interact stable synthetic exception half life years half lives day half lives minute occur products position periodic table traditionally 1940s placed group periodic table electron previous element goes results consistent set electron configurations group position disputed grounds lesser extent closer chemical properties early techniques separating rare relied distinction early group double dissolve water difficulty late ones group double water prompting researchers 1920s 1930s place instead electron goes appear argument equally valid candidates member group lighter group elements simply explained larger size expected periodic trends makes early period transition metals similar period phenomenon based poor nuclear charge added series results decrease atomic series resulting early period transition metals similar period effect makes similar shows differences smaller unlike metal core like localized compounds white solid prepared direct reaction constituent elements large size adopts coordinate structure changes coordinate structure high temperature water formed lot heat evolved reaction sound heard react carbon dioxide form basic water test presence heavier compounds produced direct reaction elements heating causes example heating produces hydrogen produce black conducting compound calcium structure non compound absorption hydrogen possible loss electrical salt like reached like probably compound large radius great contribution bonding limited coordination chemistry like dissolve metal solutions oxygen common donor complexes high coordination numbers characteristic forming square structures high coordinate species reaching coordination number use low degree symmetry factors chemistry tends involve bonding electron configuration element chemistry limited best characterised compounds complex produced reacting substituted derivatives history swedish discovered heavy mineral later named thirty years later year old family owning sent sample find new elements returned mineral jacob isolated new named dwarf planet discovered years earlier simultaneously independently isolated germany martin shown mixture swedish surgeon chemist lived house separated named partially sample air treating resulting acid properties differed slightly occurred named ancient greek lit lie hidden relatively pure metal isolated occurrence production abundant making earth crust times abundant lead earth crust despite called rare earth metals actually rare historically named common lime historically deposits known taken consideration rare earth metal process difficult time consuming expensive similarly sized early group immediately follow periodic table tends occur minerals refers rare earth metals radioactive usually lacking heavy light involved ore crushed ground treated hot concentrated acid evolving carbon dioxide hydrogen product dried water leaving early including solution procedure usually contains rare involved magnetic properties separated repeated electromagnetic separation separation treated hot concentrated acid produce water rare acidic partially solution removed solution treated convert rare converted dissolved acid main components separated double salt salt relatively rare earth double stays care taken handling contain daughter strong gamma relatively easy extract neighbouring removed making use ability state separated historical method exchange techniques higher purity desired metal obtained heating acid produce followed reduction earth metals vacuum atmosphere pure produced mixture elevated temperatures applications historical application gas von mixture called patented original gave green light successful company established factory failed modern uses include material material metal batteries high cost extract instead pure compound component type hybrid cars use metal batteries massive quantities required production hybrid automobiles typical hybrid automobile battery toyota requires kilograms engineers push technology increase fuel efficiency twice required vehicle hydrogen contain capable storing times volume hydrogen gas process heat energy released time possibilities energy conservation systems lighter contains electronic vacuum tubes hot materials strong crystals lab high extended life electron sources electron hall effect essential component heavy glass named glass superior infrared range fiber optical communication systems recent combination high light yield best energy resolution fast response high yield converts superior energy resolution light output stable high wide range temperatures making particularly attractive high temperature applications widely commercially gamma rays carbon arc lamps use mixture rare earth elements improve light quality application especially motion picture industry studio lighting projection consumed rare earth compounds produced phase carbon arc lamps iii improves resistance glass making special optical glasses infrared absorbing glass camera lenses high index low rare earth glasses grain growth liquid phase small amounts added steel improves resistance impact addition decreases sensitivity temperature variations small amounts present pool products remove feed algae gas arc substitute radioactive compounds rare earth elements etc components petroleum cracking dating estimate age rocks technique limited popularity approved medication absorb excess cases end stage failure lamp mixed applied crystal membrane selective like electron dense molecular biology modified remove water lake treatments biological role known biological role element poorly absorbed oral administration injected elimination slow approved absorb excess cases end stage disease effects channels unique acts site known negative positive native increasing open channel time decreasing configuration dependent manner precautions low moderate level handled care injection solutions produces low blood pressure alterations application carbon arc light led exposure people rare earth element led similar size easily traced substitute medical studies like known affect human lowering levels blood pressure appetite risk blood injected brain acts similarly mechanism unknown act essential