The complete combustion of salicylic acid releases 21.90 kJ of energy per gram of salicylic acid. In a particular bomb calorimeter (initially at room temperature), the combustion of 0.1182 g of salicylic acid, in the presence of excess oxygen, causes the temperature of the calorimeter to rise by 2.84 °C. When a 0.2086-g sample of an unknown organic substance is similarly burned in the same calorimeter, the temperature rises by 3.50 °C. What is the energy of combustion per unit mass of the unknown substance?

Question

please I want to see the final answer.

Answer 1

21.90 kJ/g x 0.1182 g = ?q = energy obtained by combusting salicylic acid.

Then calculate the heat capacity of the calorimeter. That is
q from above = C/degree c x 2.84 and solve for C, the heat capacity of the calorimeter.

q = heat capacity x delta T
q = Cfrom above x 3.50
Solve for q and that is q/0.2086g and that gives you q/gram of the unknown.