Video: Dab tsi yog sublimation txheej txheem?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
Sublimation yog a txheej txheem siv los ntawm chemists los purify compounds. Ib qho khoom yog feem ntau muab tso rau hauv a sublimation apparatus thiab rhuab nyob rau hauv lub tshuab nqus tsev vacuum. Nyob rau hauv qhov kev txo qis no, cov khoom volatilizes thiab condenses raws li ib tug purified compound ntawm ib tug txias nto (txias ntiv tes), tawm hauv ib tug tsis-volatile residue ntawm impurities qab.
Kuj paub yog, dab tsi yog sublimation thiab piv txwv?
Sublimation yog ib qho kev hloov pauv tshwj xeeb ntawm lub xeev thaum cov khoom siv hla cov kua theem thiab txav ncaj qha mus rau theem roj. Qhov no tshwm sim vim hais tias cov tshuaj absorbs zog sai heev los ntawm ib puag ncig uas melting yeej tsis tshwm sim. Piv txwv ntawm Sublimation : 1. "Dry ice" los yog cov khoom carbon dioxide sublimes.
Tsis tas li ntawd, thaum twg koj tuaj yeem siv txoj kev sublimation? Cov sublimation txheej txheem tuaj yeem tsuas yog siv rau ntawm 100% polyester cov ntaub ntawv los yog cov ntaub ntawv nrog ib tug tshwj xeeb polymer txheej. Sublimation yog qhov zoo tshaj plaws rau cov ntaub dawb los yog lub teeb xim. Qhov no yuav zoo li qhov kev xaiv tsawg, tab sis cov khoom siv polymer coated ua tau muaj xws li coasters, mugs, nas ncoo thiab lwm yam.
Ib tug kuj yuav nug, vim li cas sublimation tshwm sim?
Sublimation tshwm sim thaum tag nrho cov siab ntawm cov cua yog tsawg tshaj li lub vapor siab ntawm compound, thiab melting tseem tsis tau tshwm sim vim nws tsis kub txaus. Cov tebchaw sib txawv muaj qhov sib txawv vapor pressures. Melting kub yog tsim rau hauv ib yam khoom. Nws tsuas yog nyob ntawm lub ntiaj teb sab nraud xwb.
Dab tsi yog qhov piv txwv zoo ntawm sublimation?
Los ntawm sublimation , ib yam khoom hloov ntawm cov khoom mus rau ib qho roj yam tsis tau dhau los ntawm cov kua theem. Cov dej khov qhuav, cov khoom CO2, muab qhov sib txawv piv txwv ntawm sublimation . Nws tseem ua tau rau dej khov rau sublimate , txawm hais tias nws xav tau ib puag ncig huab cua tshwj xeeb thiab qhov siab siab.
Pom zoo:
Dab tsi yog qhov tseeb tom qab txheej txheem distillation?
Distillation yog cov txheej txheem tshuaj uas sib tov ua los ntawm ob lossis ntau dua cov kua (hu ua 'cov khoom') nrog cov ntsiab lus sib txawv tuaj yeem sib cais los ntawm ib leeg. Cov vapor ces muab tso rau hauv ib lub condenser, uas ua rau lub vapor txias thiab hloov nws rov qab mus rau hauv cov kua uas hu ua distillate
Cov txheej txheem ntawm kev tsim cov kev daws teeb meem yog dab tsi?
Kev daws yog tsim thaum ib yam khoom hu ua thesolute 'dissolves' rau hauv lwm yam khoom hu ua hnyav.Dissolving yog thaum lub solute tawg los ntawm ib tug loj siv lead ua ntawm molecules mus rau ntau me me los yog ib tug molecules. Lawv ua qhov no los ntawm rub tawm cov ions thiab tom qab ntawd ncig cov ntsev molecules
Koj tuaj yeem ua li cas yog tias koj tsis paub tias txheej twg yog nyob rau hauv cov txheej txheem rho tawm?
Koj tuaj yeem ua li cas yog tias koj tsis paub tias txheej twg yog nyob rau hauv cov txheej txheem rho tawm? Tso dej me me rau hauv lub caj dab ntawm qhov sib cais funnel. Ua tib zoo saib nws: yog tias nws tseem nyob hauv txheej txheej sab saud, txheej txheej ntawd yog txheej dej
Dab tsi yog txheej txheem spontaneous thiab non-spontaneous txheej txheem?
Cov txheej txheem spontaneous yog ib qho uas tshwm sim yam tsis muaj kev cuam tshuam ntawm sab nraud. Ib txoj kev uas tsis yog tshwm sim yuav tsis tshwm sim yog tias tsis muaj kev cuam tshuam ntawm sab nraud
Cov txheej txheem twg yog txheej txheem endothermic?
Cov txheej txheem endothermic yog ib qho txheej txheem uas xav tau lossis nqus lub zog los ntawm nws qhov chaw nyob ib puag ncig, feem ntau yog ua kom sov. Nws yuav yog cov txheej txheem tshuaj, xws li dissolving ammonium nitrate hauv dej, lossis cov txheej txheem ntawm lub cev, xws li melting ntawm cov dej khov nab kuab