What happens if 2 molar of HCL reacts with 2 molar of NaOH to produce H20

So 30 ml of HCL was mixed with 30 ml of NaOH making 60 ml of H20

And the heat flow in kilojoules was -3.74 kj

How would I found out the DELTA H (change in enthalpy) of kj/mol of water?

It supposed to be around -56 kj (literature value) but I don't know how to convert this?