The heat of combustion of ethanol in a bomb calorimeter at $25^{\circ}C$ is $-670.48 \, kcal \, mol^{-1}$. What is the value of $\Delta H$ for this reaction at $25^{\circ}C$ in $kcal$?

Given that bond energies of $H-H$ and $Cl-Cl$ are $430 \ kJ \ mol^{-1}$ and $240 \ kJ \ mol^{-1}$ respectively and $\Delta H_f$ for $HCl$ is $-90 \ kJ \ mol^{-1},$ the bond enthalpy of $HCl$ is ............... $kJ \ mol^{-1}$.

Identify the factor from the following on which the heat of reaction does not depend.

In the reaction $S + \frac{3}{2} O_{2} \rightarrow SO_{3} + 2x \ kJ$ and $SO_{2} + \frac{1}{2} O_{2} \rightarrow SO_{3} + y \ kJ$,the heat of formation of $SO_{2}$ is

What is the standard $N \equiv N$ bond enthalpy from the following reaction? $N_{2(g)} + 3H_{2(g)} \longrightarrow 2NH_{3(g)} \quad \Delta H^{\circ} = -83 \ kJ$
Given: $(\Delta H^{\circ}_{(H-H)} = 435 \ kJ \text{ mol}^{-1}, \Delta H^{\circ}_{(N-H)} = 389 \ kJ \text{ mol}^{-1})$

What will be the standard heat of reaction for the reaction $C_2H_{6(g)} + 7/2 O_{2(g)} \to 2CO_{2(g)} + 3H_2O_{(l)}$ if the standard heat of combustion of $C_{(s)}$ and $H_{2(g)}$ are $-393.5 \ kJ/mol$ and $-285 \ kJ/mol$ respectively,and the standard heat of formation of $C_2H_{6(g)}$ is $-88.2 \ kJ/mol$?