Question

The standard molar enthalpy of formation of NH3(g) is -45.9 kJ/mol. What is the enthalpy change if 9.51 g N 2(g) and 1.96 g H2(g) react to produce NH
3(8)?

a.-29.8 kJ/mol-rxn

b.-43.7 kJ/mol-rxn

C.-10.3 kJ/mol-rxn

d.-20.7 kJ/mol-rxn

e. -65.6 kJ/mol-rxn

Answer 1

Answer:

a. -29.8 kJ/mol-rxn

Explanation:

For a chemical reaction system the forward and reverse rate are equal. The standard molar enthalpy formation of NH3 is -45.9 kJ/mol. For the enthalpy of NH3 (8) the molar enthalpy is -29.8kJ/mol. The molar mass of N2 = 28.02g/mol. Molar enthalpy of formation is standard amount of substance produced in the formation of a reaction. The molar enthalpy is the change in enthalpy due to reaction per mole.