A calorimeter contains 27.0 grams of H2O at the temperature of 14.5 degree Celsius. When 1.40 grams of a substance that has a molar mass = 46.0 is mixed, it dissolves via the reaction and the temperature of the solution increases to 26.5 degree Celsius.Compute the enthalpy change, , for this reaction per mole of .
(Assume that the specific heat and density of the resulting solution are equal to those of water [4.18 and 1.00 ] )