The $\Delta H_f^o$ values for $ICl_{(g)}$,$Cl_{(g)}$,and $I_{(g)}$ are $17.57$,$121.34$,and $106.96 \, J \, mol^{-1}$ respectively. What is the bond dissociation energy of the $I-Cl$ bond in $J \, mol^{-1}$?

Given that the bond energies of $N \equiv N$ is $946 \ kJ \ mol^{-1}$,$H-H$ is $435 \ kJ \ mol^{-1}$,$N-N$ is $159 \ kJ \ mol^{-1}$,and $N-H$ is $389 \ kJ \ mol^{-1}$,calculate the enthalpy of formation for the gas phase reaction $N_2 + 2H_2 \rightarrow N_2H_4$ in $kJ \ mol^{-1}$.

In which of the following reactions does the heat change represent the heat of formation of water?

The heat of solution of $Na_2SO_{4(s)}$ and $Na_2SO_4 \cdot 10H_2O_{(s)}$ are $-2.34 \ kJ \ mol^{-1}$ and $78.87 \ kJ \ mol^{-1}$ respectively. The heat of hydration of $Na_2SO_{4(s)}$ is:

$PbO$ exists in two crystalline forms: yellow and red. The standard enthalpies of formation for these two forms are $-217.3 \ kJ/mol$ and $-219.0 \ kJ/mol$,respectively. Calculate the enthalpy of transition for the process: $PbO \text{ (yellow)} \rightarrow PbO \text{ (red)}$ in $kJ/mol$.

Which of the following equations represents the standard enthalpy of formation of $CH_4$?