The standard enthalpies of formation of 1,3-b | vedclass

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(A) The combustion reaction for $1,3-butadiene$ is: $C_4H_{6(g)} + \frac{11}{2} O_{2(g)} 	o 4 CO_{2(g)} + 3 H_2O_{(l)}$.First,calculate the enthalpy

Vedclass · Accepted Answer

$-650$

Vedclass · Answer

(A) The combustion reaction for $1,3-butadiene$ is: $C_4H_{6(g)} + \frac{11}{2} O_{2(g)} 	o 4 CO_{2(g)} + 3 H_2O_{(l)}$.First,calculate the enthalpy of combustion using standard enthalpies of formation: $\Delta H_c = [4 	imes \Delta H_f(CO_2) + 3 	imes \Delta H_f(H_2O_{(l)})] - \Delta H_f(C_4H_6)$.Given $\Delta H_f(H_2O_{(g)}) = -68 \ kcal/mol$ and $\Delta H_{vap}(H_2O) = 10 \ kcal/mol$,then $\Delta H_f(H_2O_{(l)}) = -68 - 10 = -78 \ kcal/mol$.Now,account for resonance energy: $\Delta H_{comb} = \Delta H_{comb(calc)} + (	ext{Resonance Energy of products} - 	ext{Resonance Energy of reactants})$.$\Delta H_{comb(calc)} = [4 	imes (-94) + 3 	imes (-78)] - (-30) = -376 - 234 + 30 = -580 \ kcal/mol$.Resonance correction: $\Delta H_{final} = -580 + (4 	imes (-20) - (-10)) = -580 - 80 + 10 = -650 \ kcal/mol$.

Similar Questions

For the reaction $2X_{(g)} + Y_{(g)} \to 2Z_{(g)}$ at $298 \ K$,$\Delta U = -10.5 \ kJ$ and $\Delta S^o = -10.5 \ J/K$. Calculate $\Delta G^o$ for the reaction. Will the reaction be spontaneous or not? Explain.

At $300 \, K$ temperature,the standard heat of formation of benzoic acid $(s)$,$CO_{2(g)}$,and $H_2O_{(l)}$ are $-408$,$-393$,and $-286 \, kJ \, mol^{-1}$ respectively. At constant pressure,the heat of combustion for benzoic acid will be $..... \, kJ$.

For a hypothetical reaction $A_{2(g)} + B_{2(g)} \rightleftharpoons 2AB_{(g)}$,at $200 \ K$,$\Delta_r G$ and $\Delta_r S$ are $20 \ kJ \ mol^{-1}$ and $-20 \ J \ K^{-1} \ mol^{-1}$ respectively. If $\Delta_r C_p = 20 \ J \ K^{-1} \ mol^{-1}$,find $\Delta_r H$ at $400 \ K$ in $kJ \ mol^{-1}$.

For the reaction $2A_{(g)} + B_{(g)} \to 2D_{(g)}$,given $\Delta U^{\theta} = -10.5 \ kJ$ and $\Delta S^{\theta} = -44.1 \ J \ K^{-1}$. Calculate $\Delta G^{\theta}$ for the reaction at $298 \ K$ and predict whether the reaction may occur spontaneously.

If standard molar enthalpy change and standard molar internal energy change measured in a bomb calorimeter are equal,which one of the following statements is correct?

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