$C + O_2 \to CO_2; \Delta H = X$
$CO + \frac{1}{2} O_2 \to CO_2; \Delta H = Y$
Then the heat of formation of $CO$ is

The heat of atomization of methane and ethane are $360 \ kJ/mol$ and $620 \ kJ/mol,$ respectively. The longest wavelength of light capable of breaking the $C-C$ bond is (Avogadro number $= 6.02 \times 10^{23},$ $h = 6.62 \times 10^{-34} \ J \cdot s$)

Consider the reaction $2H_2S(g) + 3O_2(g) \rightarrow 2H_2O(l) + 2SO_2(g)$. The magnitude of enthalpy change for the reaction in $\text{kJ mol}^{-1}$ is . . . . . . . (Nearest integer). Given: $\Delta_f H^\circ(H_2S) = -20.1 \text{ kJ mol}^{-1}$,$\Delta_f H^\circ(H_2O) = -286.0 \text{ kJ mol}^{-1}$,$\Delta_f H^\circ(SO_2) = -297.0 \text{ kJ mol}^{-1}$

The standard enthalpy of atomization of ethane according to the equation $C_2H_{6(g)} \rightarrow 2C_{(g)} + 6H_{(g)}$ is $622 \ kJ \ mol^{-1}$. If the standard mean $C-H$ bond dissociation enthalpy is $90 \ kJ \ mol^{-1}$,the standard mean dissociation enthalpy of the $C-C$ bond (in $kJ \ mol^{-1}$) is:

Calculate the standard enthalpy change of the reaction: $C_2H_{2(g)} + \frac{5}{2}O_{2(g)} \rightarrow 2CO_{2(g)} + H_2O_{(\ell)}$ given the following standard enthalpies of formation:
$\Delta_fH^{\circ}(CO_2) = -393 \ kJ \ mol^{-1}$
$\Delta_fH^{\circ}(H_2O) = -286 \ kJ \ mol^{-1}$
$\Delta_fH^{\circ}(C_2H_2) = 227 \ kJ \ mol^{-1}$

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 . . . . . . $\times 10^2 \text{ kJ mol}^{-1}$.