For the following reaction at 300 K A_2( g )+3 B_2( g ) → 2 AB_3( g ) the enthalpy change is +15 kJ, then the internal energy change is:

For the following reaction at $\displaystyle 300$ K $$\mathrm{A}_2(\mathrm{~g})+3 \mathrm{~B}_2(\mathrm{~g}) \rightarrow 2 \mathrm{AB}_3(\mathrm{~g}) $$ the enthalpy change is +$\displaystyle 15$ kJ, then the internal energy change is :