The heat of formation of $H_2O_{(l)}$ is $-68.0 \ kcal$. The heat of formation of $H_2O_{(g)}$ is likely to be........$kcal$.

The bond energy is the energy required to

The value of heat generated when $36.5 \, g$ of $HCl$ and $40 \, g$ of $NaOH$ react during neutralization is.....$kcal$.

When $2 \, mol$ of $C_2H_6$ is completely combusted,$3129 \, kJ$ of heat is released. The heat of formation of $C_2H_6$ is ..... $kJ/mol$. Given that $\Delta H_f$ for $CO_2$ and $H_2O$ are $-395 \, kJ/mol$ and $-286 \, kJ/mol$ respectively.

Identify $I, II, III$ in the given Born-Haber cycle diagram for the dissolution of an ionic solid $AB(s)$:
$AB(s) \xrightarrow{I} A^+(aq) + B^-(aq)$
$AB(s) \xrightarrow{II} A^+(g) + B^-(g)$
$A^+(g) + B^-(g) \xrightarrow{III} A^+(aq) + B^-(aq)$

The reaction for the formation of $NaCl$ is: