For which one of the following is the enthalpy of the reaction the same as the enthalpy of formation? A) 2 Fe (s) + %,02 (g) Fe,Oz (s) B) HCI (aq) NH, (g) NH;CI (s) C) AsFa (s) As (s) + %z Fz (g) D) Nz (g) 3 H; (g) NH; (9)