Given: Δ H^_sub [ C (graphite) ]=710 kJ mol^-1; Δ_C - H H^ =414 kJ mol^-1; Δ_H - H H^ =436 kJ mol^-1; Δ_C = C H^ =611 kJ mol^-1 The Δ H_f^ for CH_2=…

Given : $$\begin{aligned} & \Delta \mathrm{H}^{\ominus}{ }_{\text {sub }}[\mathrm{C} \text { (graphite) }]=710 \mathrm{~kJ} \mathrm{~mol}^{-1} \\ & \Delta_{\mathrm{C}-\mathrm{H}} \mathrm{H}^{\ominus}=414 \mathrm{~kJ} \mathrm{~mol}^{-1} \\ & \Delta_{\mathrm{H}-\mathrm{H}} \mathrm{H}^{\ominus}=436 \mathrm{~kJ} \mathrm{~mol}^{-1} \\ & \Delta_{\mathrm{C}=\mathrm{C}} \mathrm{H}^{\ominus}=611 \mathrm{~kJ} \mathrm{~mol}^{-1} \end{aligned} $$ The $\displaystyle \Delta \mathrm{H}_{\mathrm{f}}^{\ominus}$ for $\displaystyle \mathrm{CH}_2=\mathrm{CH}_2$ is $\displaystyle \_\_\_\_$ $\displaystyle \mathrm{kJ} \mathrm{mol}^{-1}$ (nearest integer value)