Video: Vim li cas thiaj li recrystallization txo cov txiaj ntsig?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
Vim li ntawd, cov teeb meem hauv qab no feem ntau tshwm sim: yog tias cov kuab tshuaj ntau dhau ntxiv rau hauv recrystallization , neeg pluag los tsis muaj tawm los ntawm crystals yuav tshwm sim. Yog hais tias cov khoom yog yaj nyob rau hauv qab ntawm lub boiling point ntawm cov tshuaj, cov kuab tshuaj ntau dhau lawm yuav tsum tau, ua rau ib tug neeg pluag. tawm los.
Ib yam li ntawd, vim li cas qhov kev daws teeb meem txias kom ua rau recrystallization?
Lub hauv paus ntsiab lus qab recrystallization yog tias tus nqi ntawm cov kuab tshuaj uas tuaj yeem yaj los ntawm qhov hnyav nce nrog qhov kub thiab txias. Thaum lub daws yog tom qab txias , tom qab filtering tawm insoluble impurities, tus nqi ntawm solute uas tseem yaj tee precipitously.
Tsis tas li ntawd, yuav ua li cas yog tias koj ntxiv cov kuab tshuaj ntau dhau thaum recrystallization? Dissolve lub solute. Yog hnyav hnyav heev yog ntxiv , cov tshuaj yuav tsis saturated thaum txias thiab tsis muaj crystals yuav tsim. Dissolving lub solute feem ntau koom nrog ntxiv ib tug me me ntim ntawm kub kuab tshuaj , swirling lub hwj (los yog nplawm cov tshuaj), thiab saib kom pom yog cov kua dissolves.
Hais txog qhov no, vim li cas yuav tsum tau tso cai rau recrystallization maj mam tshwm sim?
Kev ua kom txias qeeb ntawm cov tshuaj saturated txhawb kev tsim cov crystals ntshiab vim hais tias cov molecules ntawm impurities uas tsis haum zoo heev muaj sij hawm rov qab mus rau cov tshuaj. Cov khoom impurities yuav tsum yuav lim tau siv lub ntiajteb txawj nqus filtration txheej txheem.
Vim li cas thiaj li yuav tsum tau siv cov kuab tshuaj hauv recrystallization tsawg?
Vim li cas thiaj yuav tsum siv yam tsawg kawg nkaus xwb tus nqi ntawm qhov xav tau kuab tshuaj rau recrystallization ? Siv qhov tsawg kawg nkaus tus nqi minimizes tus tus nqi ntawm cov ntaub ntawv poob los ntawm kev khaws cia hauv kuab tshuaj . Soluble impurities yuav yaj nyob rau hauv ib kuab tshuaj , tawm hauv qab crystals ntawm ib tug ntshiab compound.
Pom zoo:
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