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The heat of combustion of ethanol into carbon dioxides and water is - 327 Kcal at constant pressure. The heat evolved (in cal) at constant volume at 27 ° C (if all gases behave ideally) is R = 2 calmol - 1 K - 1 ________

Correct answer

0

Step-by-step solution

C 2 H 5 OH ( ℓ ) + O 2 ( g ) ⟶ 2 O 2 ( g ) + 3 H 2 O ( ℓ ) ; Δ H C = - 327 Kcal Δ Hc = Δ U C + Δ n g RT - 327 × 10 3 = Δ U C + 1 × 2 × 300 Δ U C = - 326400   cal So heat evolved as constant volume is 326400 cal

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