$∆\mathrm{U}°$ $$for combustion of methane is -x kJ mol^-1.

The value of $∆\mathrm{H}°$ for the same reaction would be -

$1.$ $=$ $∆\mathrm{U}°$
$2.$ $>$ $∆\mathrm{U}°$
$3.$ $<$ $∆\mathrm{U}°$
$4.$ $=0$

The reaction of cyanamide, ${\mathrm{NH}}_2\mathrm{CN}$ $\left(\mathrm{s}\right)$ with dioxygen, was carried out in a bomb calorimeter, and ∆U was found to be $-742.7$ $\mathrm{kJ}$ ${\mathrm{mol}}^{-1}$ at 298 K.
\(\small{\mathrm{NH}_2 \mathrm{CN}(\mathrm{s})+\frac{3}{2} \mathrm{O}_2(\mathrm{g}) \rightarrow \mathrm{N}_2(\mathrm{g})+\mathrm{CO}_2(\mathrm{g})+\mathrm{H}_2 \mathrm{O}(\mathrm{l})}\)

${}_{}$The enthalpy change for the reaction at 298 K would be -

$1.$ $-741.3$ $\mathrm{kJ}$ ${\mathrm{mol}}^{-1}$
$2.$ $+$ $753.9$ $\mathrm{kJ}$ ${\mathrm{mol}}^{-1}$
$3.$ $+$ $772.$ $7$ $\mathrm{kJ}$ ${\mathrm{mol}}^{-1}$
$4.$ $-845.$ $1$ $\mathrm{kJ}$ ${\mathrm{mol}}^{-1}$

$\frac{1}{2}{N_2}_{ \left(\mathrm{g}\right)} + \frac{1}{2}{O}_{2 \left(\mathrm{g}\right)} \to N{O}_{\left(\mathrm{g}\right)} ;$
${∆}_{\mathrm{r}}H° = 90 kJ mo{l}^{-1}$
$N{O}_{\mathit{\left(}g\mathit{\right)}} + \frac{1}{2}{O_2}_{\mathit{\left(}g\mathit{\right)}} \to N{O_{\mathit{2}}}_{\mathit{\left(}g\mathit{\right)}}\hspace{0.17em};$
${∆}_{\mathrm{r}}\mathrm{H}° = -74 \mathrm{kJ} {\mathrm{mol}}^{-1}$

The thermodynamic stability of NO_(g) based on the above data is:

1. Less than NO_2(g) 

2. More than NO_2(g)

3. Equal to NO_2(g)

4. Insufficient data