Melting point yog ib yam tseem ceeb uas feem ntau siv rau cov hlau. Nws nyob ntawm ntau lub cev ntawm cov khoom - lawv cov purity thiab crystal qauv. Dab tsi hlau yog fusible tshaj plaws: Li, Al, Hg, Cu? Cia peb kawm seb leej twg tuaj yeem hu tau tiag tiag.
Muaj fusible hlau
Melting yog txheej txheem ntawm kev hloov ntawm cov khoom mus rau lub xeev ua kua. Nws tshwm sim nyob rau hauv lub zog ntawm tshav kub, tab sis kuj nyob ntawm ntau yam ntawm lub cev, xws li lub siab. Lub luag haujlwm tseem ceeb hauv kev yooj yim thiab nyuaj npaum li cas cov khoom tuaj yeem yaj tau los ntawm nws cov muaj pes tsawg leeg, qhov loj ntawm cov muaju hauv cov lattice thiab lub zog ntawm cov ntawv cog lus ntawm atoms.
Lub ntsiab lus melting ntawm cov hlau txawv heev thiab tuaj yeem muaj qhov tsis zoo. Nws nyob ntawm -39 txog +3410 degrees Celsius. Molybdenum, tungsten, chromium, titanium yog qhov nyuaj tshaj plaws los ua kua. Rau cov txheej txheem no, lawv yuav tsum tau rhuab mus rau qhov kub ntawm tsawg kawg yog 2000 degrees.
Cov hlau fusible tshaj plaws yog gallium,mercury, lithium, tin, lead, zinc, indium, bismuth, thallium. Nyeem ntxiv txog qee qhov hauv qab no.
Mercury
Siv tau ntau thaj chaw, tab sis cov hlau muaj tshuaj lom tau paub txawm tias ua ntej peb lub sijhawm. Mercury tau siv los ntawm cov kws kho mob thaum ub thiab medieval los kho venereal thiab ntau lwm yam kab mob, alchemists sim ua kom kub tawm ntawm nws. Niaj hnub no nws yog siv nyob rau hauv hluav taws xob engineering, instrumentation thiab organic chemistry.
Ruth yog cov hlau fusible tshaj plaws hauv ntiaj teb. Nyob rau hauv ib txwm chav tsev, nws yog ib txwm ua kua, txij li thaum nws melting point yog -39 degrees. Nws cov vapors yog qhov txaus ntshai heev, yog li mercury tsuas yog muaj nyob hauv cov thawv thiab cov iav tshwj xeeb. Nws ua zoo li cov tshuaj lom rau hauv lub cev, ua rau lom thiab ua rau tsis muaj zog, tiv thaiv kab mob, ua pa thiab plab zom mov.
Gallium
thib ob hauv cov npe ntawm cov hlau fusible tshaj plaws yog gallium. Nws dhau los ua cov kua dej ntawm qhov kub siab tshaj 29.5 degrees Celsius, thiab koj tuaj yeem muag nws tsuas yog tuav nws me ntsis ntawm koj txhais tes. Nyob rau hauv ib txwm muaj mob, gallium yog nkig heev, yooj yim mechanically cuam tshuam thiab muaj lub teeb silvery, me ntsis xiav xim.
Cov hlau tawg heev nyob rau hauv lub ntiaj teb crust thiab tsis pom nyob rau hauv daim ntawv ntawm nuggets. Nyob rau hauv cov xwm, nws muaj nyob rau hauv muaj pes tsawg leeg ntawm ntau yam minerals, xws li garnet, muscovite, tourmaline, chlorite, feldspar. Tsis tas li ntawd, nws muaj nyob hauv dej hiav txwv. Gallium yog siv nyob rau hauv high-frequency electronics, rau kev tsim cov iav thiab ntau yam alloys.
India
Raws li cov khoom siv yooj yim, indium yog lub teeb heev, tuaj yeem yooj yim, thiab muag muag txaus txawm tias tawm ntawm lub cim thaum rub hla daim ntawv. Nws kuj yog ib qho ntawm cov hlau fusible tshaj plaws, tab sis tsuas yog cuam tshuam los ntawm qhov kub siab tshaj 157 ° C. Nws boils ntawm 2072 degrees.
Zoo li gallium, indium tsis tsim nws tus kheej tso nyiaj, tab sis muaj nyob rau hauv ntau yam ores. Vim nws dispersion nyob rau hauv cov xwm, cov hlau yog kim heev. Nws yog siv rau hauv microelectronics, rau kev tsim cov alloys uas tsis tshua muaj melting, solders, kua siv lead ua cov ntxaij vab tshaus rau technology.
Tin
Tin melts ntawm qhov kub siab tshaj 231 degrees Celsius. Nws yog cov hlau nplaum thiab mos, lub teeb nyiaj hauv cov xim. Nws muaj nyob rau hauv plaub qhov kev hloov kho allotropic, ob qho uas tshwm sim tsuas yog thaum muaj kev kub ntxhov.
Tin yog qhov sib txawv heev hauv cov xwm txheej, tab sis tuaj yeem tsim nws cov minerals xws li stannin thiab cassiterite. Nws yog siv los ua cov txheej txheem hlau los txhim kho lawv cov kev tiv thaiv corrosion, nrog rau kev tsim cov tin, ntawv ci, ntau yam alloys, tais diav thiab qhov chaw rau cov twj paj nruag.
Lithium
Lithium yog cov hlau fusible tshaj plaws, uas dhau los ua kua ntawm qhov kub ntawm 180 degrees. Nws yog mos, qiv nws tus kheej zoo rau forging thiab machining. Nws belongs rau alkali hlau, tab sis tsis tshua muaj zog tshaj li lwm pab pawg neeg. Nws reacts maj mam nrog huab cua noo, thiab nyob rau hauv ib qho chaw qhuav yuav luagruaj khov
Cov hlau muaj nyob rau hauv spodumene, lepidolite, nyob rau hauv deposits nrog tin, bismuth thiab tungsten, pom nyob rau hauv dej hiav txwv thiab nyob rau hauv stellar qhov chaw khoom. Lithium feem ntau yog siv rau kev tsim cov galvanic hlwb, roj teeb, siv los ua tus neeg sawv cev oxidizing, nrog rau hauv pyrotechnics. Nyob rau hauv alloys nrog cadmium, tooj liab thiab txhuas, nws yog siv nyob rau hauv qhov chaw, tub rog thiab aviation technology.
