Answer to Question #146177 in General Chemistry for Jessica Mafo

Question

Given the heats of reactions, calculate the change in enthalpy for the reaction P4O10(s) + 6PCl5(g) -->10Cl3PO(g).

P4(s) + 6Cl2 (g) --> 4PCl3(g) enthalpy change -1225.6 KJ

P4(s) + 5O2(g) --> P4O10 (s) enthalpy change - 2697.3 KJ

PCl3 (g) + Cl2 (g) --> PCl5 (g) enthalpy change - 84.2 KJ

PCl3(g) + 1/2 O2(g) --> Cl3PO(g) enthalpy change -285.7

Answer 1

∆H=10 x(-285.7) -(-2697.3+6x(-84.2)=

=345,5 kJ.