A quantity of 3.30 × 102 mL of 0.500 M HNO3 is mixed with 3.30 × 102 mL of 0.250 M Ba(OH)2 in a constant-pressure calorimeter of negligible heat capacity. The initial temperature of both solutions is the same at 18.46°C. The heat of neutralization when 1.00 mol of HNO3 reacts with 0.500 mol Ba(OH)2 is −56.2 kJ/mol. Assume that the densities and specific heats of the solution are the same as for water (1.00 g/mL and 4.184 J/g · °C, respectively). What is the final temperature of the solution?
q = mass H2O x specific heat H2O x Tfinal-Tinitial)
56,200 J = 660 g x 4.184 J/g*C x (Tfinal-18.46)
Solve for Tfinal. Post your work if you get stuck.