Enthalpies of formation of $CCl_{4(g)}$,$H_2O_{(g)}$,$CO_{2(g)}$ and $HCl_{(g)}$ are $-105$,$-242$,$-394$ and $-92 \ kJ \ mol^{-1}$ respectively. The magnitude of enthalpy of the reaction given below is $...... \ kJ \ mol^{-1}$ (nearest integer): $CCl_{4(g)} + 2H_2O_{(g)} \rightarrow CO_{2(g)} + 4HCl_{(g)}$

In the reaction $H_2 + Cl_2 \rightarrow 2HCl$,heat is released. The bond energies of $H-H$ and $Cl-Cl$ are $430 \ kJ \ mol^{-1}$ and $242 \ kJ \ mol^{-1}$ respectively. If the enthalpy of reaction is $-182 \ kJ \ mol^{-1}$,the bond energy of $H-Cl$ is . . . . . . $kJ \ mol^{-1}$.

Average $C-H$ bond energy is $416 \ kJ \ mol^{-1}$. Which of the following is correct?

Which substance has a standard molar enthalpy of formation equal to zero at $298 \ K$?

Calculate the enthalpy of formation of ethylene $(C_2H_4)$ from the following data:
$I. C_{(graphite)} + O_{2(g)} \rightarrow CO_{2(g)}; \Delta H = -393.5 \ kJ$
$II. H_{2(g)} + \frac{1}{2}O_{2(g)} \rightarrow H_2O_{(l)}; \Delta H = -286.2 \ kJ$
$III. C_2H_{4(g)} + 3O_{2(g)} \rightarrow 2CO_{2(g)} + 2H_2O_{(l)}; \Delta H = -1410.8 \ kJ$ (in $kJ$)

Calculate the enthalpy change for the following reaction, using the given bond energies $(\text{kJ/mol})$: $C-H = 414$, $H-O = 463$, $H-Cl = 431$, $C-Cl = 326$, and $C-O = 335$.
$CH_3OH(g) + HCl(g) \rightarrow CH_3Cl(g) + H_2O(g)$