Chemistry Question?

Question

10. Phosphorus trichloride (PCl3) reacts with hydrochloric acid to produce chlorine gas and phosphine
(PH3):
PCl3 (g) + 3 HCl (g) ? 3 Cl2(g) + PH3 (g) DHrxn = +570.4 kJ
The enthalpies of formation of some compounds are listed in the table below.
Substance DHf (kJ/mol) Substance DHf (kJ/mol)
PCl3 (g) -288.1 H2O, liquid -285.8
HCl (g) -92.3 H2O, gas -241.8
Based on the data provided the enthalpy of formation of gaseous phosphine, PH3 (g), is _____.

The answer is 5.4 Kilojoules per mole but how do you figure it out??

Answer 1

570.4-(288+3*92.3)