Question

The combustion of 0.1572 g benzoic acid increases the temperature of a bomb calorimeter by 2.52°C. Calculate the heat capacity of this calorimeter. (The energy released by combustion of benzoic acid is 26.42 kJ/g.)
What is the heat capacity in kJ/C? = 1.65 kJ/C


A 0.2197-g sample of vanillin (C8H8O3) is then burned in the same calorimeter, and the temperature increases by 3.28°C. What is the energy of combustion per gram of vanillin?
Energy in kJ/gram?

I know how to find the heat capacity, but I keep getting the energy incorrect.

Answer 1

are you certain about the mass of benzoic acid? .1572g is a very small amount.
heatenergy= grams*1.65kJ/g=.1572*26.42 kJ/g= = 4.153 kJ or 4153J

second one: energy=Heatcapacity*changetemp

energy= 1.65kJ/c*3.28C=5.41kJ or 5410J
energycomputstion= 5.41kJ/.2195g = ..

Answer 2

What would be the correct number of sig figs?

Answer 3

three sig figs, or course