Question

Calculate the enthalpy of reaction for the following:

N2 + 3H2 -> 2NH3 they are all gases.

Is this reaction endothermic or exothermic?

Answer 1

Look up delta Hf values in your text or notes, then calculate
deltaHrxn = (n*DHproducts)-(DHreactants).
The sign is - for exothermic; + for endothermic.

Answer 2

Thanks!

Answer 3

I omitted an n in that. It should be
deltaHrxn = (n*DHfproducts) - (n*DHfreactants)