Qhov sib txawv tseem ceeb ntawm ebullioscopic tas li thiab cryoscopic tas li yog tias ebullioscopic tas li yog cuam tshuam nrog qhov kub ntawm qhov nce siab ntawm ib yam khoom thaum lub sijhawm cryoscopic tas li cuam tshuam rau qhov chaw txias txias ntawm cov khoom.
Ebullioscopic tas li thiab cryoscopic tas li yog cov ntsiab lus siv feem ntau hauv cov thermodynamics los piav txog cov khoom ntawm ib yam khoom uas cuam tshuam txog kev hloov pauv ntawm qhov kub thiab txias. Ob qhov tas mus li no muab tus nqi tib yam rau ib yam khoom ntawm cov xwm txheej zoo sib xws ntawm txoj kev sib txawv.
Ebullioscopic Constant yog dab tsi?
Ib qho ebullioscopic tas li yog ib lub sij hawm thermodynamic uas cuam tshuam cov molality ntawm ib yam khoom rau nws qhov kub siab tshaj qhov siab. Peb tuaj yeem txheeb xyuas qhov ebullioscopic tas li li Kb, qhov kub nce siab li ΔT thiab molality li "b". Qhov tsis tu ncua yog muab raws li qhov sib piv ntawm qhov kub ntawm qhov nce siab thiab molality (boiling point elevation faib los ntawm molality sib npaug ebullioscopic tas li, Kb). Peb tuaj yeem muab qhov kev qhia lej rau qhov tsis tu ncua raws li hauv qab no:
ΔT=iKbb
Hauv qhov sib npaug no, "i" yog Van't Hoff yam. Nws muab cov naj npawb ntawm cov kuab tshuaj tuaj yeem faib ua lossis tsim thaum cov tshuaj yaj hauv cov kuab tshuaj. "b" yog molality ntawm cov tshuaj tsim tom qab no dissolution. Ntxiv rau qhov kev sib npaug yooj yim no, peb tuaj yeem siv lwm qhov kev qhia lej los xam qhov ebullioscopic tas li theoretically:
Kb=RT2bM/ ΔHvap
Hauv qhov sib npaug no, R yog hais txog qhov zoo tagnrho (lossis universal) roj tas li, Tb yog hais txog qhov kub ntawm qhov hnyav, M yog hais txog cov molar loj ntawm cov kuab tshuaj, thiab ΔH vapyog hais txog cov molar enthalpy ntawm vaporization. Txawm li cas los xij, hauv kev suav cov molar loj ntawm ib yam khoom, peb tuaj yeem siv tus nqi paub rau qhov tsis tu ncua uas siv cov txheej txheem hu ua ebullioscopy. Ebullioscopy yog hais txog "kev ntsuas kub" hauv Latin lub ntsiab lus.
Daim duab 01: Kev Nyuaj Siab Tshaj Plaws thiab Boiling Point Elevation hauv daim duab
Cov cuab yeej ntawm qhov siab ntawm qhov kub kub yog suav tias yog cov khoom sib koom ua ke uas cov cuab yeej nyob ntawm seb muaj pes tsawg cov khoom tawg rau hauv cov kuab tshuaj thiab tsis yog qhov xwm txheej ntawm cov khoom. Qee qhov paub qhov tseem ceeb rau ebullioscopic tas li suav nrog acetic acid muaj 3.08, benzene muaj 2.53, camphor muaj 5.95, thiab carbon disulfide muaj 2.34.
Cryoscopic Constant yog dab tsi?
Ib qho chaw cia li cryoscopic yog ib lub sij hawm thermodynamic uas cuam tshuam cov molality ntawm ib yam khoom mus rau qhov chaw txias txias. Kev nyuaj siab qhov chaw khov kho kuj yog cov khoom sib txuam ntawm cov khoom. Lub cryoscopic tas mus li yuav muab tau raws li hauv qab no:
ΔTf=iKfb
Ntawm no, "i" yog Van't Hoff yam, uas yog tus naj npawb ntawm cov kuab tshuaj tuaj yeem faib ua lossis tuaj yeem tsim thaum yaj hauv cov kuab tshuaj. Cryoscopy yog tus txheej txheem uas peb tuaj yeem siv los txiav txim siab qhov ua rau lub cev tsis tu ncua ntawm ib yam khoom. Peb tuaj yeem siv qhov paub tsis tu ncua los xam qhov tsis paub molar loj. Lo lus cryoscopy los ntawm Greek lub ntsiab lus, "kev ntsuas khov".
Vim tias qhov chaw khov kho kev nyuaj siab yog cov cuab yeej sib koom ua ke, nws tsuas yog nyob ntawm tus lej ntawm cov ntsiab lus uas tau yaj thiab tsis nyob ntawm qhov xwm txheej ntawm cov khoom ntawd. Yog li, peb tuaj yeem hais tias cryoscopy muaj feem xyuam nrog ebullioscopy. Kev qhia lej rau qhov tsis tu ncua yog raws li hauv qab no:
Kb=RT2fM/ ΔHfus
R yog qhov zoo tagnrho cov pa tsis tu ncua, M yog cov molar loj ntawm cov kuab tshuaj, Tf yog qhov khov ntawm cov kuab tshuaj ntshiab thiab ΔH fusyog molar enthalpy ntawm fusion ntawm cov kuab tshuaj.
Qhov txawv ntawm Ebullioscopic Constant thiab Cryoscopic Constant yog dab tsi?
Ebullioscopic tas li thiab cryoscopic tas li yog cov ntsiab lus siv hauv thermodynamics. Qhov sib txawv tseem ceeb ntawm ebullioscopic tas li thiab cryoscopic tas li yog tias ebullioscopic tas li muaj feem xyuam rau qhov kub ntawm qhov nce siab ntawm cov khoom thaum lub sij hawm cryoscopic tas mus li muaj feem xyuam rau qhov chaw txias txias ntawm ib yam khoom.
Hauv qab infographic qhia txog qhov sib txawv ntawm ebullioscopic tas li thiab cryoscopic tas li.
Summary – Ebullioscopic Constant vs Cryoscopic Constant
Qhov sib txawv tseem ceeb ntawm ebullioscopic tas li thiab cryoscopic tas li yog tias ebullioscopic tas li yog cuam tshuam nrog qhov kub ntawm qhov nce siab ntawm ib yam khoom thaum lub sijhawm cryoscopic tas li cuam tshuam rau qhov chaw txias txias ntawm cov khoom.
