For $NaCl_{(s)}$,the enthalpy of solution is $4 \ kJ \ mol^{-1}$ and the lattice enthalpy is $790 \ kJ \ mol^{-1}$. What is the hydration enthalpy of $NaCl$?

Calculate the standard enthalpy change for the reaction,$C_2H_5OH_{(\ell)} + 3O_{2_{(g)}} \rightarrow 2CO_{2_{(g)}} + 3H_2O_{(\ell)}$. Given: $\Delta_{f}H^{\circ}(C_2H_5OH) = -280 \ kJ \ mol^{-1}$,$\Delta_{f}H^{\circ}(CO_2) = -390 \ kJ \ mol^{-1}$,and $\Delta_{f}H^{\circ}(H_2O) = -285 \ kJ \ mol^{-1}$.

Given the following thermochemical equations:
$(i)$ $H_{2(g)} + \frac{1}{2}O_{2(g)} \rightarrow H_2O_{(l)}; \Delta H = -285 \text{ kJ}$
$(ii)$ $N_2O_{5(g)} + H_2O_{(l)} \rightarrow 2HNO_{3(l)}; \Delta H = -76.6 \text{ kJ}$
$(iii)$ $N_{2(g)} + 3O_{2(g)} + H_{2(g)} \rightarrow 2HNO_{3(l)}; \Delta H = -348.2 \text{ kJ}$
Calculate the $\Delta H$ for the reaction: $2N_{2(g)} + 5O_{2(g)} \rightarrow 2N_2O_{5(g)}$. (in $\text{ kJ}$)

The heat of neutralization of a strong dibasic acid by a dilute solution of $NaOH$ is approximately ....... $Kcal/equivalent$.

Which of the following reactions defines the standard enthalpy of combustion,$\Delta H_c^ \circ$?

For the reaction $Cl_{2(g)} \rightarrow 2Cl_{(g)}$,the value of $\Delta H$ is .......