Hydrogen reacts with chlorine to form hydrogen chloride (HCl (g), Delta. Hf = –92. 3 kJ/mol) according to the reaction below. Upper H subscript 2 (g) plus upper C l subscript 2 (g) right arrow 2 upper H upper C l (g). Which statement is correct? Use Delta H r x n equals the sum of delta H f of all the products minus the sum of delta H f of all the reactants. The enthalpy of the reaction is –184. 6 kJ, and the reaction is exothermic. The enthalpy of the reaction is –184. 6 kJ, and the reaction is endothermic. The enthalpy of the reaction is 184. 6 kJ, and the reaction is endothermic. The enthalpy of the reaction is 184. 6 kJ, and the reaction is exothermic.