Yam 56: Barium

1. Elemental Taw qhiaBarium,
Lub ntiaj teb alkaline hlau, nrog rau cov cim tshuaj Ba, yog nyob rau hauv pab pawg IIA ntawm lub thib rau lub sij hawm ntawm lub periodic rooj. Nws yog ib tug mos, silver dawb luster alkaline ntiaj teb hlau thiab lub feem ntau active caij nyob rau hauv alkaline ntiaj teb hlau. Lub npe lub npe los ntawm Greek lo lus beta alpha ρύς (barys), uas txhais tau tias "hnyav".

barium pob

 

2. Tshawb nrhiav keeb kwm luv luv
Sulfides ntawm alkaline ntiaj teb hlau pom phosphorescence, txhais tau tias lawv tseem emit lub teeb rau ib lub sij hawm ntawm qhov tsaus ntuj tom qab raug rau lub teeb. Barium tebchaw pib nyiam tib neeg txoj kev xav paub meej vim yog tus yam ntxwv no. Xyoo 1602, ib tug kws tsim khau hu ua Casio Lauro nyob hauv nroog Bologna, Ltalis, tau ci ib qho barite uas muaj barium sulfate ua ke nrog cov khoom siv hluav taws xob thiab pom tias nws tuaj yeem tawm teeb pom kev hauv qhov tsaus ntuj, uas ua rau muaj kev txaus siab ntawm cov kws tshawb fawb thaum lub sijhawm ntawd. Tom qab ntawd, hom pob zeb no hu ua polonite thiab aroused qhov kev txaus siab ntawm European chemists nyob rau hauv analytical kev tshawb fawb. Xyoo 1774, Swedish chemist CW Scheele pom tias barium oxide yog cov av tshiab hnyav, uas nws hu ua "Baryta" (hnyav av). Xyoo 1774, Scheler ntseeg tias lub pob zeb no yog kev sib xyaw ntawm cov av tshiab (oxide) thiab sulfuric acid. Xyoo 1776, nws tau tso cov nitrate hauv cov av tshiab no kom tau cov av ntshiab (oxide). Xyoo 1808, British chemist H. Davy siv mercury li cathode thiab platinum ua anode rau electrolyze barite (BaSO4) los tsim barium amalgam. Tom qab distillation kom tshem tawm cov mercury, cov hlau tsis huv tau txais thiab muaj npe tom qab Greek lo lus barys (hnyav). Lub cim cim yog teem li Ba, uas yog hu uabarium.

3. Lub cev muaj zog
Bariumyog ib tug silver dawb hlau nrog ib tug melting point ntawm 725 ° C, boiling point ntawm 1846 ° C, ceev ntawm 3.51g / cm3, thiab ductility. Lub ntsiab ores ntawm barium yog barite thiab arsenopyrite.

tus lej atomic 56
proton naj npawb 56
atomic radius 222pm ua
atomic ntim 39.24 cm ib3/mol
kub point 1846 ℃
Melting point 725 ℃
Qhov ntom 3.51g / cm33
atomic luj 137.327 ib
Mohs hardness 1.25
Tensile modulus 13gp ua
shear modulus 4.9gp ua
thermal expansion 20.6 µm / (m·K) (25 ℃)
thermal conductivity 18.4 W / (m·K)
tiv taus 332 nΩ·m (20 ℃)
Sib nqus ib ntus Paramagnetic
electronegativity 0.89 (Bowling nplai)

4,Bariumyog cov khoom siv tshuaj lom neeg nrog cov khoom siv tshuaj lom neeg.
Cov cim tshuaj lom neeg Ba, atomic naj npawb 56, belongs rau lub sij hawm IIA pawg thiab yog ib tug tswv cuab ntawm alkaline ntiaj teb hlau. Barium muaj cov tshuaj lom neeg ua haujlwm zoo thiab yog qhov nquag tshaj plaws ntawm alkaline ntiaj teb hlau. Los ntawm lub peev xwm thiab ionization zog, nws tuaj yeem pom tias barium muaj zog txo qis. Qhov tseeb, yog tias tsuas yog xav txog qhov poob ntawm thawj electron, barium muaj qhov txo qis tshaj plaws hauv dej. Txawm li cas los xij, nws yog qhov nyuaj rau barium kom poob lub electron thib ob. Yog li ntawd, xav txog txhua yam, qhov txo qis ntawm barium yuav txo qis. Txawm li cas los xij, nws kuj yog ib qho ntawm cov hlau reactive tshaj plaws hauv cov kua qaub, thib ob tsuas yog lithium, cesium, rubidium, thiab potassium.

Lub voj voog 6
Cov pab pawg neeg IIA
Electronic txheej txheej 2-8-18-18-8-2 ib
oxidation xeev 0 +2
Peripheral electronic layout 6s2 ib

5.Main compounds
1). Barium oxide maj mam oxidizes hauv huab cua los tsim barium oxide, uas yog ib qho tsis muaj xim cubic crystal. Soluble nyob rau hauv acid, insoluble nyob rau hauv acetone thiab ammonia dej. Reacts nrog dej los tsim barium hydroxide, uas yog tshuaj lom. Thaum hlawv, nws tawm cov nplaim ntsuab thiab tsim barium peroxide.
2). Barium peroxide reacts nrog sulfuric acid los tsim hydrogen peroxide. Cov tshuaj tiv thaiv no yog ua raws li lub hauv paus ntsiab lus ntawm kev npaj hydrogen peroxide hauv chav kuaj.
3). Barium hydroxide reacts nrog dej los tsim barium hydroxide thiab hydrogen gas. Vim tias qhov tsis tshua muaj solubility ntawm barium hydroxide thiab nws lub zog sublimation siab, cov tshuaj tiv thaiv tsis yog khaus li cov hlau alkali, thiab cov txiaj ntsig barium hydroxide yuav ua rau pom qhov pom. Ib qho me me ntawm cov pa roj carbon dioxide tau nkag mus rau hauv cov kev daws teeb meem los ua ib qho barium carbonate precipitate, thiab cov pa roj carbon dioxide ntau ntxiv tau qhia ntxiv kom yaj cov barium carbonate precipitate thiab tsim cov dej soluble barium bicarbonate.
4). Amino barium tuaj yeem yaj hauv cov kua ammonia, tsim cov tshuaj xiav nrog paramagnetism thiab conductivity, uas tseem ceeb tsim cov ammonia electrons. Tom qab lub sijhawm ntev ntawm kev cia, hydrogen hauv ammonia yuav raug txo kom hydrogen gas los ntawm ammonia electrons, thiab tag nrho cov tshuaj tiv thaiv yog barium reacting nrog kua ammonia los tsim cov amino barium thiab hydrogen gas.
5). Barium sulfite yog siv lead ua dawb lossis hmoov, tshuaj lom, me ntsis soluble hauv dej, thiab maj mam oxidized rau hauv barium sulfate thaum muab tso rau hauv huab cua. Dissolve nyob rau hauv tsis oxidizing muaj zog acids xws li hydrochloric acid los tsim sulfur dioxide gas nrog ib tug pungent tsw. Thaum ntsib oxidizing acids xws li dilute nitric acid, nws tuaj yeem hloov mus rau barium sulfate.
6). Barium sulfate muaj cov tshuaj ruaj khov, thiab ib feem ntawm barium sulfate yaj hauv dej yog ionized kiag li, ua rau nws muaj zog electrolyte. Barium sulfate yog insoluble nyob rau hauv dilute nitric acid. Feem ntau yog siv los ua tus neeg sawv cev ntawm lub plab zom mov.
Barium carbonate yog tshuaj lom thiab yuav luag insoluble hauv dej txias., me ntsis soluble hauv dej uas muaj carbon dioxide thiab soluble hauv dilute hydrochloric acid. Nws reacts nrog sodium sulfate los tsim ib tug ntau insoluble dawb precipitate ntawm barium sulfate - kev hloov pauv ntawm precipitates nyob rau hauv aqueous tov: nws yog ib qho yooj yim mus hloov mus rau ib tug ntau insoluble kev taw qhia.

6 、 Daim ntawv thov teb
1. Nws yog siv rau kev lag luam hauv kev tsim cov ntsev barium, alloys, foob pob hluav taws, nuclear reactors, thiab lwm yam. Nws kuj yog ib qho zoo heev deoxidizer rau refining tooj liab. Siv dav hauv cov hlau, xws li txhuas, calcium, magnesium, sodium, lithium, aluminium, thiab nickel alloys. Barium hlau tuaj yeem siv los ua tus neeg saib xyuas degassing kom tshem tawm cov kab hluav taws xob los ntawm lub tshuab nqus tsev thiab cov kab hluav taws xob cathode, nrog rau tus neeg saib xyuas degassing rau refining hlau. Barium nitrate sib xyaw nrog potassium chlorate, magnesium hmoov, thiab rosin tuaj yeem siv los tsim cov teeb liab flares thiab foob pob hluav taws. Soluble barium compounds feem ntau yog siv los ua tshuaj tua kab, xws li barium chloride, los tswj ntau yam kab tsuag. Nws tseem tuaj yeem siv rau kev ua kom zoo brine thiab boiler dej rau electrolytic caustic soda ntau lawm. Kuj tseem siv tau los npaj cov pigments. Cov textile thiab tawv industries siv nws raws li ib tug mordant thiab ib tug matting tus neeg saib xyuas rau dag dag.
2. Barium sulfate rau kev kho mob yog ib qho tshuaj pab rau kev kuaj X-ray. Cov hmoov dawb tsis muaj ntxhiab thiab saj tsis qab, ib yam khoom uas tuaj yeem muab qhov zoo sib xws hauv lub cev thaum kuaj X-ray. Kev kho mob barium sulfate tsis nqus rau hauv plab hnyuv thiab tsis ua rau muaj kev fab tshuaj. Nws tsis muaj cov kuab tshuaj lom neeg xws li barium chloride, barium sulfide, thiab barium carbonate. Feem ntau yog siv rau kev kuaj mob plab, qee zaus siv rau lwm yam kev kuaj mob

7 、 Txoj kev npaj
Kev lag luam ntau lawm ntawmhlau bariummuab faib ua ob kauj ruam: kev tsim cov barium oxide thiab hlau thermal txo (txheej aluminium thermal txo). Ntawm 1000-1200 ℃,hlau bariumtuaj yeem tau txais los ntawm kev txo cov barium oxide nrog hlau aluminium, thiab tom qab ntawd lim los ntawm lub tshuab nqus tsev distillation. Aluminium thermal txo txoj kev tsim cov hlau barium: Vim muaj qhov sib txawv ntawm cov khoom sib txawv, tej zaum yuav muaj ob qho kev cuam tshuam rau txhuas txo cov barium oxide. Qhov sib npaug ntawm cov tshuaj tiv thaiv yog: ob qho tib si cov tshuaj tiv thaiv tsuas tuaj yeem tsim tau me me ntawm barium ntawm 1000-1200 ℃. Yog li ntawd, lub tshuab nqus tsev twj tso kua mis yuav tsum tau siv txuas ntxiv hloov barium vapor los ntawm thaj chaw tshuaj tiv thaiv mus rau qhov chaw txias condensation kom cov tshuaj tiv thaiv txuas ntxiv mus rau sab xis. Cov seem tom qab cov tshuaj tiv thaiv yog tshuaj lom thiab yuav tsum tau kho ua ntej muab pov tseg


Post lub sij hawm: Sep-12-2024