Video: Delta H ntawm h20 yog dab tsi?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
Yog vim li cas std. enthalpy hloov kev tsim rau H2O (l) exothermic ntau dua li ntawm H2O (g)? enthalpy ntawm formation rau H2O (l)(-285.8kJ/mol) yog me dua qhov ntawd rau H2O (g)(-241.82kJ/mol). Hauv ib lo lus, cov theem sib txawv ntawm cov khoom muaj teeb meem thaum tham txog std.
Kuj nug, dab tsi yog tus qauv enthalpy ntawm h2o?
Cov tshuaj inorganic
| Hom | Theem | ΔfH? /(kJ/mol) |
|---|---|---|
| Dej | Ua kua | −285.8 |
| Hydrogen ion | Aqueous | 0 |
| Hydroxide ion | Aqueous | −230 |
| Hydrogen peroxide | Ua kua | −187.8 |
Qhov thib ob, qhov kub ntawm kev tsim cov dej ua kua yog dab tsi? Enthalpy ntawm kev tsim cov kua ntawm cov txheej txheem (nominally 298.15 K, 1 atm.)
| ΔfH°ua kua (kJ/mol) | -285.83 |
| Txoj kev | Saib xyuas |
| Kev siv | Cais, 1998 |
| Saib | |
|---|---|
| Cov ntaub ntawv kawg tshuaj xyuas thaum lub Peb Hlis, 1979 | |
Kuj tseem paub, dab tsi yog qhov enthalpy ntawm vaporization ntawm dej?
40.65 kJ/mol
Koj txhais li cas enthalpy?
Enthalpy yog ib qho khoom siv thermodynamic ntawm ib qho system. Nws yog tus lej ntawm lub zog sab hauv ntxiv rau cov khoom ntawm lub siab thiab ntim ntawm qhov system. Nws qhia txog lub peev xwm ua haujlwm tsis yog siv tshuab thiab lub peev xwm tso tawm cua sov. Enthalpy yog denoted li H; tshwj xeeb enthalpy npe h.
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