The heat evolved during the combination of $24 \, g$ of $C$ and $128 \, g$ of $S$ according to the reaction $C + 2S \to CS_2$ with $\Delta H = 22.0 \, kcal$ is:

At $25$ $^\circ C$ and $1$ $atm$ pressure,the enthalpies of formation of $C_2H_4(g)$,$CO_2(g)$,and $H_2O(l)$ are $52$,$-394$,and $-286 \, kJ \, mol^{-1}$ respectively. The enthalpy of combustion of $C_2H_4$ is ....... $kJ \, mol^{-1}$.

The enthalpy of sublimation of $I_{2(s)}$ is $57.3 \, kJ \, mol^{-1}$ and the enthalpy of fusion is $15.5 \, kJ \, mol^{-1}$. The enthalpy of vaporization of $I_2$ is ..................... $kJ \, mol^{-1}$. (in $.8$)

$A$ sample of $n$-octane $(1.14 \ g)$ was completely burnt in excess of oxygen in a bomb calorimeter,whose heat capacity is $5 \ kJ \ K^{-1}$. As a result of the combustion reaction,the temperature of the calorimeter increased by $5 \ K$. The magnitude of the heat of combustion of octane at constant volume is $.......... \ kJ \ mol^{-1}$ (nearest integer).

The molar enthalpy change for $H_2O_{(l)} \rightleftharpoons H_2O_{(g)}$ at $373 \ K$ and $1 \ atm$ is $41 \ kJ \ mol^{-1}$. Assuming ideal behavior,the internal energy change for vaporization of $1 \ mol$ of water at $373 \ K$ and $1 \ atm$ in $kJ \ mol^{-1}$ is:

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.