Chemistry - Thermochemistry Question with Solution | TestHub

${\text{N}}_{\text{2}}\text{+}\frac{\text{1}}{\text{2}}{\text{O}}_{\text{2}}\to {\text{N}}_{\text{2}}\text{O;}\text{ΔH}\text{=}\text{28 kJ}$…(i)
$\frac{\text{1}}{\text{2}}{\text{N}}_{\text{2}}\text{+}\frac{\text{1}}{\text{2}}{\text{O}}_{\text{2}}\to \text{NO;}\text{ΔH}\text{=}\text{90}\text{kJ}$…(ii)
By equation [4$\times$(ii)] – [2$\times$(i)],
$2{\mathrm{N}}_2\mathrm{O}+{\mathrm{O}}_2\to 4\mathrm{N}\mathrm{O}$
$\mathrm{\Delta }\mathrm{H}=360-56$
$\mathrm{\Delta }\mathrm{H}=\mathrm{304\; kJ}$.