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 $K \, cal$?

Which of the following is (are) an endothermic reaction?

The heat change for the following reaction at $298 \ K$ and at constant pressure is $+ 7.3 \ kcal$. $A_2B_{(s)} \to 2A_{(s)} + 1/2 \ B_{2(g)}$,$\Delta H = + 7.3 \ kcal$. The heat change at constant volume would be

The reversible expansion of an ideal gas under adiabatic and isothermal conditions is shown in the figure. Which of the following statement$(s)$ is (are) correct?
$(A)$ $T_1 = T_2$
$(B)$ $T_3 > T_1$
$(C)$ $W_{\text{isothermal}} > W_{\text{adiabatic}}$
$(D)$ $\Delta U_{\text{isothermal}} > \Delta U_{\text{adiabatic}}$

The molar heat capacity for an ideal gas at constant pressure is $20.785 \ J \ K^{-1} \ mol^{-1}$. The change in internal energy is $5000 \ J$ upon heating it from $300 \ K$ to $500 \ K$. The number of moles of the gas is [Nearest integer] (Given: $R = 8.314 \ J \ K^{-1} \ mol^{-1}$)

The standard entropies of $X_2$,$Y_2$,and $XY_3$ are $60$,$40$,and $50 \ J \ K^{-1} \ mol^{-1}$ respectively. For the reaction $\frac{1}{2}X_2 + \frac{3}{2}Y_2 \to XY_3$,$\Delta H = -30 \ kJ$ at equilibrium. What is the temperature of the system in $K$?