Heat of combustion of $CH_4, C_2H_4$ and $C_2H_6$ are $-890, -1411$ and $-1560 \ kJ/mol$ respectively. Which has the lowest calorific value?

For which of the following thermodynamic processes is $\Delta U = 0$?

For the reaction $CO_{(g)} + \frac{1}{2}O_{2_{(g)}} \rightarrow CO_{2_{(g)}}$ at $17^o C$ and constant volume,the heat of reaction is $-67.71 \, K \, cal$. What is the heat of reaction at constant pressure at $17^o C$ in $K \, cal$?

For the reaction $2X_{(s)} + 2Y_{(s)} \to 2C_{(\ell)} + D_{(g)}$,the value of $q_p$ is $-28 \, \text{kcal mol}^{-1}$ at $2700 \, ^\circ\text{C}$. Calculate the value of $q_v$ in $\text{kcal mol}^{-1}$.

The heat of combustion of sucrose $(C_{12}H_{22}O_{11})$ is $1350 \ kcal \ mol^{-1}$. How much heat (in $kcal$) will be released by the combustion of $17.1 \ g$ of sucrose (in $.5$)?

How much $kJ$ energy is released when $6 \ mol$ of octane is burnt in air? Given $\Delta H_f^o$ for $CO_{2(g)}$,$H_2O_{(g)}$ and $C_8H_{18(l)}$ respectively are $-490$,$-240$,and $+160 \ kJ/mol$.