Chemistry Calcultions

Calculate ΔH⁰298  (in kJ) for the process P(s) + 5/2 Cl2(g) → PCl5(g)from the following information.P(s) + 3/2Cl2(g) → PCl3(g) ΔH⁰298  = −287 kJ PCl3(g) +Cl2(g) → PCl5(g) ΔH⁰298  = −88 kJ