The enthalpy of formation of CO _ (g) , CO _ 2(g), N ₂ O _ (g) and N ₂ O _ 4(g) is -110,-393,+811 and 10 ~kJ / mol respectively. For the reaction, N ₂ O _ 4(g) +3 CO _ (g) N ₂ O _ (g) +3 CO _ 2(g) ; H_r( ~kJ / mol ) is

Step-by-step solution

aligned & N ₂ O _ 4(g) +3 CO _ (g) N ₂ O _ (g) +3 CO _ 2( ~g ) & H_ reaction = _ Heat of formation of products &- _ Heat of formation of reactants aligned aligned & H_ reaction = [ H_f ~N ₂ O +3 H_f CO ₂ ]- & [ H_f ~N ₂ O ₄+3 H_f CO ] & aligned H_r & =[+811+3(-393)]-[10+3(-110)] & =[811-1179]-[-320]=-368+320 & =-48 ~kJ / mol aligned aligned