Video: Yuav siv sublimation li cas los ntxuav cov khoom?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
Sublimation yog ib txoj kev siv los ntawm chemists rau ua kom huv tshuaj sib xyaw. A khov kho feem ntau yog muab tso rau hauv a sublimation apparatus thiab rhuab nyob rau hauv lub tshuab nqus tsev vacuum. Nyob rau hauv no txo siab, lub khov kho volatilizes thiab condenses li a purified compound nyob rau ntawm qhov chaw txias (txias ntiv tes), tawm hauv qhov tsis muaj volatile residue ntawm impurities qab.
Ntawm no, cov tshuaj dab tsi tuaj yeem ua kom huv los ntawm sublimation?
Sublimation yog cov txheej txheem uas cov organic tebchaw (feem ntau yog cov khib nyiab) ncaj qha hloov mus rau lub xeev vapor los ntawm cov khoom-lub xeev yam tsis tau mus txog lub xeev cov kua hauv nruab nrab. Cov txheej txheem no muaj txiaj ntsig zoo rau cov tebchaw xws li benzoic acid, camphor, naphthalene thiab ntau ntau volatile compounds.
Ib yam li ntawd, cov txheej txheem ntawm sublimation yog dab tsi? Sublimation yog hom kev hloov pauv, lossis hloov pauv hauv lub xeev ntawm cov teeb meem, ib yam li melting, khov, thiab evaporation. 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, khoom CO2, muab ib qho piv txwv ntawm sublimation.
Nyob rau hauv tas li ntawd, yuav ua li cas sublimation thiab recrystallization dawb ib yam khoom los ntawm impurities?
Hauv Sublimation , ib tug yog muab tso rau hauv ib lub nkoj uas yog ces cua sov. Nyob rau hauv qhov txo qhov siab no cov khoom volatilizes thiab condenses raws li ib tug purified compound ntawm ib tug cooledsurface, tawm hauv lub non-volatile. impurities qab.
Vim li cas sublimation hla cov kua theem?
Lub zog raug tshem tawm thaum lub sijhawm sublimation . Qhov no yog cov txheej txheem uas cov roj hloov ncaj qha mus rau ib qho khoom tsis tau mus txog qhov ua kua xeev. Nws tshwm sim thaum cov pa roj cua txias heev. Vim li cas sublimation tshwm sim muaj ua nrog rau inter-molecular rog hauv cov khoom.
Pom zoo:
Yuav ua li cas koj paub thaum twg yuav siv cov khoom los yog quotient txoj cai?
Kev faib ua haujlwm. Yog li, thaum twg koj pom kev sib faib ntawm ob txoj haujlwm, siv txoj cai khoom thiab nyob rau hauv rooj plaub ntawm kev faib siv txoj cai quotient. Yog tias muaj nuj nqi muaj ob qho kev sib faib thiab faib, tsuas yog siv ob txoj cai raws li. Yog tias koj pom qhov sib npaug dav nws yog ib yam zoo li, qhov twg yog qhov ua haujlwm ntawm ib leeg
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