Answer to Question #201908 in Inorganic Chemistry for AG SERUMULA

Question

The reaction of 1.00 mol of solid phosphorus with chlorine gas to form PCl3(g) releases 287.0 kJ of heat energy. The reaction of 1.00 mol of solid phosphorus with chlorine gas to form PCl5(g) releases 374.9 kJ of heat energy. Using Hess’s law, indirectly calculate the enthalpy change (in kJ.mol-1 ) for the following reaction. [8 punte. / 8 marks.] PCl3 (g) + Cl2 (g) → PCl5 (g) 

Answer 1

states that regardless of the multiple stages or steps of a reaction, the total enthalpy change for the reaction is the sum of all changes

Enthalpy change = $287+374.9$

=661.9 kJ