Alejandro L. answered 08/09/16
Chemistry tutor (all areas) + Intro Astronomy
the combined mass of the solution is 40.0 g (NaOH) + 36.5 g (HCl) + 100 g (H2O) = 176.5 g solution
the formula to determine the total energy released upon neutralization is:
q = mass x specific heat x change in temperature
q = (176.5 g) x (4.184 J/gC) x (110.5 - 22 C) = 72.74 kJ
therefore, the total enthalpy of reaction is 72.74 kJ/mol because only one mole of reagent was used.