Question

N2+ 3H2 GIVES 2NH3 = -90.5

4NH3+5O2 GIVES 4NO+6H20 =-905.1
H2 +0.5 O2 GIVES H2O =-241.1

USE THESE VALUES TO DETERMINE ENTHALPHY CHANGES

Answer 1

Enthalpy changes of what?

I assume those values are kJ/mol.