What is the change in enthalpy for the following reaction?


4NH3(g) + 302(g) 2N2(g) + 6H2O(l)


Given:

NH3: ∆H= -46.2 kJ

Given: H2O: ∆H= -286 kJ

A-1530.4 kJ
B-1020.3 kJ
C1530.4 kJ
D1020.3 kJ
E-510.1 kJ

Verified Answer :

c...........................................................



Answer;

A. -1530.4 kJ

Explanation;

  • Enthalpy change is the amount of heat evolved or absorbed in a chemical reaction at a constant pressure. It is abbreviated as delta H or ΔH.
  • The enthalpy change is a result of the difference between the sum of internal energy of the products and the sum of internal energy of the reactants.

Since; NH3: ∆H= -46.2 kJ

          H2O: ∆H= -286 kJ

Then; ΔH = 4(-46.2) + 3(-286)

      = -1530.4 kJ

This means the reaction is exothermic as ΔH is negative.