Yuav ua li cas yog lub khov kub ntawm lub cawv?

Nyob rau hauv raws li cov kev txhais, cov khov taw tes yog qhov kub thiab txias kev hloov ntawm ib yam khoom uas los ntawm ib tug kua hauv lub xeev mus rau ib tug khoom. Qhov no yam ntxwv nyob rau hauv dab tsi yam khoom uas yog txias (muaj pes tsawg leeg) thiab nyob li cas siab, raws li ntau dua qhov lub siab, lub siab khov kub. Qhov tseem zoo-paub tshuaj uas yog feem ntau xa mus los ntawm cov kua rau khoom thiab vice versa, yog dej. Nws yog lub npe hu hais tias zoo tib yam dej ua dej khov ntawm xoom degrees Celsius, txawm li cas los, ultrapure H ₂ O nyob rau hauv ib tug huv txog ntsha yuav tsum yog ib tug ua kua thiab nyob rau hauv mob loj heev te, raws li zoo raws li lub hiav txwv, muaj ib tug plurality ntawm ntsev.

Lwm yam kua muaj ntau yam kev kawm. Piv txwv li, haus dej cawv khov taw tes qis tshaj cov tib metric dog dig dej. Qhov no yog vim lub fact tias qhov no cov ntaub ntawv uas muaj ib tug sab ceev.

Nyob rau hauv tag nrho cov muaj ntau ntau pab pawg ntawm cov alcohols, txhua tus uas muaj nws tus kheej lub cev thiab tshuaj zog. Niaj hnub no, lawv yog cov nram qab no cov chav kawm:

- nyob ntawm seb lub xov tooj ntawm hydroxyl pawg (los ntawm monohydric rau polyhydric alcohols) ;

- nyob ntawm seb yuav ua li cas noo hydrocarbon substituent (unsaturated, txwv, uas muaj ntxhiab);

- nyob ntawm seb ib tug cyclic hydrocarbon substituent (alicyclic, cyclic);

- lub xov tooj ntawm substituents nyob rau alpha carbon atom (thawj - tertiary).

Piv txwv li, lub freezing point ntawm methanol cawv, hais txog monohydric yog rho tawm 97 degrees celsius thiab cyclohexanol - txog rho tawm 42 ° ^C. Txawm li cas los, feem ntau cov kev tshawb fawb xyaw tshwm cov lus nug hais txog cov thaj chaw ntawm cov kua, ib feem ntawm cov dej cawv. Lub khov kub ntawm ethyl cawv (ethanol) yog rho tawm 114 degrees celsius. Qhov no tej khoom vaj tse yog siv nyob rau hauv lub tsev mus rau ntsiab lub cawv tivthaiv ntawm dej cawv haus nyob rau hauv thiaj li yuav "ua rau kom cov neeg kawm ntawv", raws li zoo raws li rau zus tau tej cov lub caij ntuj no "nezamerzayki" rau lub tsheb. Ib txhia neeg tsav tsheb ntxiv rau ib tug iav-ethanol kev daws teeb meem ntawm lub caij ntuj sov hom, los yog tov nrog dej nyob rau hauv tej yam proportions.

Nco ntsoov tias tsis yog txhua txhua ntawm cov kua nyob rau hauv cov hoob kawm no muaj nyob rau hauv ib tug khoom hauv lub xeev tsuas nrog ib tug heev muaj zog txias. Piv txwv li, haus dej cawv khov taw tes phenyl carbinol (benzyl uas muaj ntxhiab cawv) yog rho tawm 15 ° ^C.

Yog hais tias koj puas tau yuav xav nyob rau hauv lub cais ntawm thermometers koj yuav pom hais tias muaj tus ntsuas mob, khiav rau cawv. Xws li es tsis txhob ntawm lub tshuab hluav taws xob mechanism los yog ntaus ntawv muaj mercury nyob rau hauv dej cawv. Cov thermometers yog feem ntau siv qhov twg nws yog tsim nyog los ntsuas tus nqi qis tshaj kub nyob rau hauv lub domestic ib puag ncig. Piv txwv li, nyob rau hauv Siberia, qhov twg heev frosts mus txog 50-60 degrees. Ntawm no zoo tib yam nyob hauv tus ntsuas yuav tsis ua hauj lwm zoo vim hais tias ntawm mercury khov kub yog hais txog rho tawm 38 ^° C Kawm txog dab tsi koj muaj ib tug pas ntsuas kub, koj yuav tau muaj xim nyob rau hauv sab ntawm tus pas ntsuas kub. Yog hais tias nws yog nyiaj, lub mercury hauv. Tab sis cov liab bar qhia Tinted cawv tov. Tej thermometers yog feem ntau siv los ntsuas lwm kub. Txawm hais tias txoj kev yuav -45 ^{° C,} tus xauj tsev yuav tsis tsis, vim hais tias cawv khov kub yog qis.