Question

0.500 g of graphite (elemental carbon) is reacted with oxygen in a bomb calorimeter filled with water, which has a total heat capacity of 2820 J/^oC. If the reaction gave off 16.4 kJ and the initial temperature of the water and calorimeter was 22.40 ^oC, what should the final temperature be? I got 34.031 when i tried it using q=mc(tf-ti) and it was wrong. I really need to learn this so as much work as you can help me with, the better.