Question

Assume that no heat is lost to the surroundings and calculate the enthalpy involved when 200. mL of .10 M potassium hydroxide and 200. mL of .10 M hydrochloric acid are mixed. Both solutions began at room temperature, 24.5 degrees celsius, and have densities very close to 1.00 g/mL. The highest temperature reached when the two solutions were mixed was 31.0 degrees celsius. Assume that the specific heat of the solution is equal to that of water, 4.184 J/g times K

Answer 1

You don't ask a question. I assume the problem is to determine the heat of neutralization in kJ/mol. Also, I assume there is no calorimeter constant so we ignore that.
Please check the post to make sure you have all of it correctly. The answer should be about 55 kJ/mol and it isn't coming out to that.