Question

Consider the following reaction: 2 Mg + O2 → 2 MgO ΔH rxn = -1203 kJ
Calculate the amount of heat (in kJ) associated with complete reaction of 4 moles of Mg.

How do I set this up correctly?

Answer 1

Assuming O2 is in excess:

2 moles of MgO=2 moles of Mg=1 moles of O2

So,

4 moles of Mg*(-1203kJ/2 moles of Mg)=???

Answer 2

2406