Given that heats of combustion of ethylene, hydrogen and ethane are -337.0, -68.4 and -373.0 kcal respectively at 25° C , the heat of reaction C2H4(.g.)+H2(.g.) arrow C2H6(.g) at 25° C will be

Question

Given that heats of combustion of ethylene, hydrogen and ethane are -337.0, -68.4 and -373.0 kcal respectively at 25° C , the heat of reaction C2H4(.g.)+H2(.g.) arrow C2H6(.g) at 25° C will be (A) -32.4 kcal (B) -36.3 kcal (C) -37.8 kcal (D) -39.2 kcal

Tardigrade Admin · Accepted Answer

Δ Hr x n= Sigma Δ Hc (Reactants) - Sigma Δ Hc (Products) = (- 337.0 textkcal - 68.4 textkcal) - (- 373 textkcal) =(.-337.0-68.4+373.)kcal=-32.4 kcal .

Q. Given that heats of combustion of ethylene, hydrogen and ethane are -337.0, -68.4 and -373.0 kcal respectively at $2 5^{\circ} C$ , the heat of reaction

$C_{2} H_{4} (g) + H_{2} (g) \to C_{2} H_{6} (g)$ at $2 5^{\circ} C$ will be

-32.4 kcal

-36.3 kcal

-37.8 kcal

-39.2 kcal

$Δ H_{r x n} = ΣΔ H_{c}$ (Reactants) $- ΣΔ H_{c}$ (Products)

$= (- 337.0 kcal - 68.4 kcal) - (- 373 kcal)$

$= (- 337.0 - 68.4 + 373) k c a l = - 32.4 k c a l$ .

Q. Given that heats of combustion of ethylene, hydrogen and ethane are -337.0, -68.4 and -373.0 kcal respectively at 25∘C , the heat of reaction C2​H4​(g)+H2​(g)→C2​H6​(g) at 25∘C will be