Question $30$ of $33$

Determine the enthalpy of reaction for $2C{H}_4(g)C_2{H}_4(g)+2H_2(g)$ using the equations:

$2C_2{H}_6(g)+7O_2(g)4C{O}_2(g)+6H_{2}O(l)H=-3120\mathrm{.}8k\frac{J}{m}ol$

$C{H}_4(g)+2O_2(g)C{O}_2(g)+2H_{2}O(l)H=-890\mathrm{.}3k\frac{J}{m}ol$

$C_2{H}_4(g)+H_2(g)C_2{H}_6(g)H=-136\mathrm{.}3k\frac{J}{m}ol$

$H_2(g)+\frac{1}{2}{O}_2(g)H_{2}O(l)H=-285\mathrm{.}8k\frac{J}{m}ol$