1. The problem statement, all variables and given/known data The combustion of hydrazine, N2H4, produces nitrogen gas and water vapor. The heat of combustion for this reaction is -618 kJ/mol. If 1.6 g of hydrazine are combusted in a bomb calorimeter at 298 K and with a heat capacity of 6.2 kJ/C, what will be the temperature of the bomb calorimeter after the reaction? Answer: 303 K 2. Relevant equations Q=CΔT 3. The attempt at a solution We're given ΔH, which is -618 kJ/mol. Thus 1.6 grams of hydrazine is 0.05 mol. Multiplying ΔH and mol gives me the heat evolved (Q) = -30.9 kJ. Setting up the equation, I get: Q=CΔT -30.9 kJ = (6.2 kJ/C)(Tf-25) Tf = 20 C Converting this to Kelvin, I get 293 K. What did I do wrong here? I think that I am confusing ΔH and Q?