Qhov txawv ntawm qhov muaj peev xwm kub thiab qhov kub tshwj xeeb

2024 Tus sau: Alex Aldridge | [email protected]. Kawg hloov kho: 2023-12-17 13:40

Qhov sib txawv tseem ceeb ntawm qhov muaj peev xwm kub thiab cov cua kub tshwj xeeb yog qhov muaj peev xwm kub yog nyob ntawm cov khoom siv, thaum lub peev xwm tshwj xeeb yog ywj siab ntawm nws.

Thaum peb sov cov khoom, nws qhov kub thiab txias, thiab thaum peb txias nws, nws qhov kub thiab txias. Qhov sib txawv ntawm qhov kub thiab txias no yog proportional rau tus nqi ntawm cov khoom cua sov. Thaum tshav kub kub muaj peev xwm thiab cov cua kub tshwj xeeb yog ob qhov sib npaug sib npaug uas cuam tshuam rau qhov kub thiab txias hloov thiab qhov kub npaum li cas.

Lub peev xwm kub yog dab tsi?

Hauv cov thermodynamics, tag nrho lub zog ntawm lub cev yog lub zog sab hauv. Internal zog qhia tag nrho cov kinetic thiab muaj peev xwm zog ntawm molecules nyob rau hauv lub system. Peb tuaj yeem hloov lub zog sab hauv ntawm lub cev los ntawm kev ua haujlwm ntawm lub kaw lus lossis los ntawm cua sov. Lub zog sab hauv ntawm ib yam khoom nce thaum peb nce nws qhov kub thiab txias. Tus nqi nce yog nyob ntawm cov xwm txheej uas cov cua sov tshwm sim. Ntawm no, peb xav tau cua sov kom kub.

Lub peev xwm kub (C) ntawm ib yam khoom yog qhov kom muaj cua sov xav tau los nce qhov kub ntawm cov khoom los ntawm ib qho degree Celsius (los yog ib qho kelvin). Thaum tshav kub kub muaj peev xwm txawv ntawm cov khoom mus rau cov khoom. Tus nqi ntawm cov khoom yog ncaj qha proportional rau lub tshav kub muaj peev xwm. Qhov ntawd txhais tau hais tias los ntawm ob npaug ntawm qhov loj ntawm cov khoom, lub peev xwm kub ua ob npaug. Qhov cua sov peb yuav tsum tau nce qhov kub ntawm t₁ rau t_{2 ntawm ib yam khoom tuaj yeem suav nrog siv qhov sib npaug hauv qab no.}

q=C x ∆t

q=xav tau cua sov

∆t=t₁-t₂

Daim duab 01: Lub peev xwm ntawm Helium

Chav ntsuas kub yog JºC^-1 lossis JK^{-1. Ob hom hluav taws xob muaj peev xwm txhais tau tias nyob rau hauv thermodynamics; Thaum tshav kub kub muaj peev xwm ntawm lub siab tas li thiab lub peev xwm kub ntawm qhov ntim tas li.}

Qhov Kub Kub Kub yog dab tsi?

Lub peev xwm kub yog nyob ntawm tus nqi ntawm cov khoom. Cov cua kub tshwj xeeb lossis cov peev txheej kub tshwj xeeb (s) yog lub peev xwm ua kom sov uas tsis muaj zog ntawm cov khoom siv. Peb tuaj yeem txhais nws li "qhov ntau ntawm cov cua sov yuav tsum tau nce qhov kub ntawm ib gram ntawm cov khoom los ntawm ib degree Celsius (los yog ib Kelvin) ntawm lub siab tas li."

Chav ntsuas kub tshwj xeeb yog Jg^-1oC^-1 Cov dej kub tshwj xeeb yog siab heev, nrog tus nqi ntawm 4.186 Jg^-1oC^{-1 Qhov no txhais tau tias, kom nce qhov kub ntawm 1 g ntawm dej los ntawm 1 ° C, peb xav tau 4.186 J ntawm lub zog cua sov.. Tus nqi siab no suav nrog lub luag haujlwm ntawm cov dej hauv thermal tswj. Txhawm rau nrhiav cov cua sov uas xav tau los ua kom qhov kub thiab txias ntawm ib qho khoom loj ntawm t1 txog t2, cov kab zauv hauv qab no tuaj yeem siv.}

q=m x s x ∆t

q=xav tau cua sov

m=pawg ntawm cov khoom

∆t=t₁-t₂

Txawm li cas los xij, qhov sib npaug saum toj no tsis siv yog tias cov tshuaj tiv thaiv cuam tshuam nrog kev hloov pauv theem; Piv txwv li, thaum dej mus rau theem roj (ntawm lub boiling point), los yog thaum dej khov los ua dej khov (ntawm lub melting point). Qhov no yog vim qhov kub ntxiv lossis tshem tawm thaum lub sijhawm hloov pauv tsis hloov qhov kub.

Qhov txawv ntawm qhov muaj peev xwm kub thiab qhov kub tshwj xeeb yog dab tsi?

Qhov sib txawv tseem ceeb ntawm qhov muaj peev xwm kub thiab cov cua kub tshwj xeeb yog qhov muaj peev xwm kub yog nyob ntawm cov khoom siv thaum lub peev xwm kub tshwj xeeb yog ywj siab ntawm nws. Tsis tas li ntawd, thaum xav txog txoj kev xav, lub peev xwm ntawm cov cua sov yuav tsum tau hloov cov khoom kub los ntawm 1 ° C los yog 1K thaum cov cua kub tshwj xeeb yog qhov kub uas yuav tsum tau hloov 1g ntawm cov khoom kub los ntawm 1 ° C los yog 1K.

Summary – Thaum tshav kub kub vs tshwj xeeb kub

Lub peev xwm kub thiab cov cua sov tshwj xeeb yog cov ntsiab lus tseem ceeb hauv thermodynamics. Qhov sib txawv tseem ceeb ntawm qhov muaj peev xwm kub thiab cov cua kub tshwj xeeb yog qhov muaj peev xwm kub yog nyob ntawm cov khoom siv thaum lub peev xwm tshwj xeeb yog ywj siab ntawm nws.