Comment on the thermodynamic stability of $NO_{(g)}$,given:
$\frac{1}{2} N_{2(g)} + \frac{1}{2} O_{2(g)} \rightarrow NO_{(g)}; \Delta_r H^{\ominus} = 90 \, kJ \, mol^{-1}$
$NO_{(g)} + \frac{1}{2} O_{2(g)} \rightarrow NO_{2(g)}; \Delta_r H^{\ominus} = -74 \, kJ \, mol^{-1}$

State Hess's Law of Constant Heat Summation.

Combustion of $1$ $mol$ of benzene is expressed as:
$C_6H_{6(l)} + \frac{15}{2} O_{2(g)} \rightarrow 6CO_{2(g)} + 3H_2O_{(l)}$
The standard enthalpy of combustion of $2$ $mol$ of benzene is $-x$ $kJ$.
$x = . . . . . . . . . .$
$(1)$ Standard enthalpy of formation of $1$ $mol$ of $C_6H_{6(l)}$ is $48.5$ $kJ \ mol^{-1}$.
$(2)$ Standard enthalpy of formation of $1$ $mol$ of $CO_{2(g)}$ is $-393.5$ $kJ \ mol^{-1}$.
$(3)$ Standard enthalpy of formation of $1$ $mol$ of $H_2O_{(l)}$ is $-286$ $kJ \ mol^{-1}$.

Based on Hess's law calculations,what is the average bond energy of $S-O$ in $SO_3$ if $\Delta H_f^o$ of $SO_3$ is $-270 \ kJ \ mol^{-1}$. The bond energy of $O=O$ is $495 \ kJ \ mol^{-1}$ and the heat of sublimation for $S_{(s)}$ is $277 \ kJ \ mol^{-1}$? (Given: Bond energy of $S=O$ is not provided,assume the reaction $S_{(s)} + \frac{3}{2} O_2(g) \rightarrow SO_3(g)$). Note: The provided values in the prompt were inconsistent with standard chemical data; using standard values: $\Delta H_{sub}(S) = 277 \ kJ \ mol^{-1}$,$BE(O=O) = 495 \ kJ \ mol^{-1}$,$BE(S-O) = 330 \ kJ \ mol^{-1}$ is not the goal,we calculate based on the provided logic.

Molar enthalpy of combustion of $C_2H_{2(g)}$,$C_{(s)}$,and $H_{2(g)}$ are $-1300$,$-394$,and $-286 \ kJ/mol$ respectively. The standard enthalpy of formation of $C_2H_{2(g)}$ is $:$

The enthalpy of atomisation for the reaction $CH_{4(g)} \to C_{(g)} + 4H_{(g)}$ is $1665 \ kJ \ mol^{-1}$. What is the bond energy of $C-H$ bond?