If the bond energies of $H-H$,$Br-Br$ and $H-Br$ are $433$,$192$ and $364 \ kJ \ mol^{-1}$ respectively,the $\Delta H^o$ for the reaction,$H_{2(g)} + Br_{2(g)} \to 2HBr_{(g)}$ is.....$kJ$

If the enthalpies of atomization of methane and ethane are respectively $320 \ cal$ and $360 \ cal$,then the bond energy of the $C-C$ bond is......$cal$.

Enthalpy of sublimation of a substance is equal to

The bond dissociation energies of gaseous $H_2$,$Cl_2$ and $HCl$ are $104$,$58$ and $103 \ kcal$ respectively. The enthalpy of formation of $HCl$ gas would be $... \ kcal$.

From the given data at $298 \, K$:
$\Delta H_f^o [CO_2, g] = -394 \, kJ/mol$
$\Delta H_f^o [H_2O, l] = -286 \, kJ/mol$
$\Delta H_f^o [propene, g] = 20 \, kJ/mol$
$cyclopropane (g) \to propene (g)$; $\Delta H^o_{isomerisation} = -33 \, kJ/mol$.
Calculate $\Delta H^o_{combustion} [cyclopropane, g]$.
$...... \, kJ/mol$

If $3.365 \text{ g}$ of ethanol $(l)$ is burnt completely in a bomb calorimeter at $298.15 \text{ K}$, the heat produced is $99.472 \text{ kJ}$. The $|\Delta H_f^\circ|$ of ethanol at $298.15 \text{ K}$ is . . . . . . $\times 10^2 \text{ kJ mol}^{-1}$.