Chemistry question about calculating enthalpy?

Question

anonymous · Answer

Foam cup A has 36 mL of water that contains 2 moles of HCl at 20 degrees Celsius. Foam cup B has 36 mL of water that contains 2 moles of NaOH at 20 degrees Celsius. The contents of foam cup A are added to foam cup B and a chemical reaction occurs. The final temperature of the contents of cup B is 31 degrees Celsius.
I need to calculate the enthalpy change of the reaction. The density of both solutions is 1 g/mL. I really don't understand how to calculate enthalpy, and my textbook doesn't really say how to. I don't need the exact answer, but if someone could teach me the steps with this problem, that would be great.

anonymous · Answer

sorry this was supposed to be in chemistry