Calculate ΔH vap [CH 3 COOH(l)] in kJ/mol from the following data: ΔH Solution [CsF·CH 3 COOH(s)] in glacial acetic acid = -5 kJ/mol; ΔH Solution [CsF(s)] in glacial acetic acid = +33 kJ/mol; the stre

Question

Calculate ΔH vap [CH 3 COOH(l)] in kJ/mol from the following data: ΔH Solution [CsF·CH 3 COOH(s)] in glacial acetic acid = -5 kJ/mol; ΔH Solution [CsF(s)] in glacial acetic acid = +33 kJ/mol; the strength of H-bond between F - (g) and CH 3 COOH(g) = +50 kJ/mol; lattice enthalpy of CsF·CH 3 COOH(s) = +740 kJ/mol; lattice enthalpy of CsF(s) = +801 kJ/mol.

TestHub · Accepted Answer

Let CsF(s) + CH 3 COOH(l) → CsF·CH 3 COOH(s) have ΔH 1 . Both solids give the same solution: ΔH 1 + (-5) = 33, so ΔH 1 = +38 kJ. Cycle: ΔH 1 + 740 = 801 + ΔH vap - 50, so 778 = 751 + ΔH vap and ΔH vap = 27 kJ/mol. The answer is 0027.

Chemistry - Thermochemistry Question with Solution | TestHub

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