NH$3($g$)=-46\mathrm{.}11$kJ$/$mol PRACTICE EXAMPLE B: How is $H$ for the following reaction related to the standard enthalpy of formation of $N{H}_3(g)$ listed in Table $7\mathrm{.}2?$ What is the value of $H=?$

$2N{H}_3(g)longrightarrow{N}_2(g)+3H_2(g),H=$