Video: Dab tsi yog qhov enthalpy ntawm c2h5oh?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
Txuj enthalpies ntawm formation yog: C2H5OH (l) -228, CO2 (g) -394, thiab H2O (l) -286 kJ / mol.
Ib yam li ntawd, tib neeg nug, dab tsi yog qhov enthalpy ntawm kev tsim ntawm ethanol?
Teeb meem #17: (a) Tus qauv enthalpy ntawm kev tsim ntawm ethanol , C2H5OH(ℓ), yog −278 kJ mol¯1.
Tsis tas li ntawd, dab tsi yog qhov enthalpy ntawm kev tsim ntawm nh4cl? Xaiv ATcT enthalpy ntawm kev tsim raws li version 1.118 ntawm Thermochemical Network
| Hom Lub Npe | Formula | ΔfH° (298.15 K) |
|---|---|---|
| Ammonium chloride | (NH4) Cl (cr) | -314.892 |
Kuj Paub, qhov kab zauv twg sawv cev rau tus qauv enthalpy ntawm kev tsim rau ethanol c2h5oh?
Muab rau standard enthalpies ntawm kev tsim ( C2H5OH (l) = -267.0 kJ/mol, H2O (g) = -241.8 kJ/mol, thiab CO2 (g) = -393.5 kJ/mol), pes tsawg grams ethanol Yuav tsum tau combusted kom tso tawm 30.5 kJ ntawm lub zog?
Dab tsi yog delta H RXN rau combustion ntawm ethanol?
Enthalpy ntawm combustion
| Tshuaj | Combustion Reaction | Enthalpy ntawm Combustion, ΔH∘c(kJmolat 25∘C) |
|---|---|---|
| ethanol | C2H5OH(l)+3O2(g)?2CO2(g)+3H2O(l) | −1366.8 |
| methanol | CH3OH(l)+32O2(g)?CO2(g)+2H2O(l) | −726.1 |
| isooctane | C8H18(l)+252O2(g)?8CO2(g)+9H2O(l) | −5461 |
| Table 2. Standard Molar Enthalpies ntawm Combustion | ||
Pom zoo:
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