Chemistry
posted by Jake .
Given:
H3PO4(aq) + 3 NaOH(aq) ¨ 3 H2O(l) + Na3PO4(aq)
ƒ¢H = 166.5 kJ
What is the value for q (heat) if 4.00 g of NaOH reacts with an excess of H3PO4?
Please can you explain to me HOW to do this, not just give me an answer?
Thanks!

The heat of reaction has the wrong units...it should be 166.5kJ/MoleNa3PO4
So, the question is, the reaction calls for three moles (120g) of NaOH, so you will get 4/120 fraction of the heat of reaction. 
Given:
H3PO4(aq) + 3 NaOH(aq) yields 3 H2O(l) + Na3PO4(aq)
change in H = 166.5 kJ
What is the value for q (heat) if 4.00 g of NaOH reacts with an excess of H3PO4?
Please can you explain to me HOW to do this, not just give me an answer?
Thanks!