$2.2 \, g$ of nitrous oxide $(N_{2}O)$ gas is cooled at a constant pressure of $1 \, atm$ from $310 \, K$ to $270 \, K$ causing the compression of the gas from $217.1 \, mL$ to $167.75 \, mL$. The change in internal energy of the process,$\Delta U$ is $-x \, J$. The value of $x$ is $....$ [nearest integer] (Given: atomic mass of $N = 14 \, g \, mol^{-1}$ and of $O = 16 \, g \, mol^{-1}$. Molar heat capacity of $N_{2}O$ is $100 \, J \, K^{-1} \, mol^{-1}$)

One mole of $CH_3OH$ is vaporized at $338 \ K$ and $1.5 \ atm$ pressure. If the enthalpy of vaporization of $CH_3OH$ is $35.57 \ kJ/mol$,calculate the value of $\Delta U$ for the process in $kJ$. (in $.76$)

Calculate $\Delta S_{total}$ for the following reaction at $300 \ K$.
$NH_4NO_{3(s)} \longrightarrow NH_4^+{(aq)} + NO_3^-{(aq)}$ $(\Delta H = 28.1 \ kJ \ mol^{-1}, \Delta S_{sys} = 108.7 \ J \ K^{-1} \ mol^{-1})$

$A$ mixture of $H_2$ and a sufficient quantity of air at $25\,^{\circ}C$ and $1\ atm$ pressure undergoes complete combustion in a closed rigid adiabatic container,leaving behind $H_2O_{(g)}$ and $N_{2(g)}$. If air is a mixture of $80\% N_2$ and $20\% O_2$ by volume and $C_{P(N_2)}$ and $C_{P(H_2O)g}$ are $7.0$ and $8.0\ cal\ deg^{-1}\ mol^{-1}$ respectively,what will be the maximum temperature attained? (Given that: $(\Delta H^o_f)_{H_2O_{(g)}} = -56.0\ kcal/mol$ and it is independent of temperature)...... $K$

Which of the following is true for the reaction $H_2O_{(l)} \rightleftharpoons H_2O_{(g)}$ at $100 ^oC$ and $1 \text{atm}$ pressure?

The enthalpy of formation of $H_2O$ is $-68 \ k.cal/mol$. Calculate the enthalpy of formation of $OH^-$. Given that the enthalpy of neutralization of $H^+$ and $OH^-$ is $-13.7 \ k.cal/mol$.