Calorimeter

[105691548]

I am still a little confused on how specific heat capacity can be calculated by a calorimeter, could someone give a brief explanation?

[Mariko Hashimoto 2I]

I think with the equation: qp = ΔH = g Cp ΔT we can typically solve for the specific heat capacity of a substance. For instance, in a constant pressure calorimeter you can make a chemical reaction in the water. Calculate how much the temperature of the water changes due to the reaction, and then plug that the mass of water (not substance), temp change, and specific heat of water (known to be 4.18 J/Cg) to get the energy given off by the reaction (will be positive since everything in the equation is positive). With this new qp value of the surroundings, solve for the specific heat using the qp = ΔH = g Cp ΔT equation again, but plug the qp value in as negative, since we are now analyzing the energy of the system, not surroundings. The negative temp change and negative qp(sys) will cause the calculated Cp to be positive.

[Shivani Sakthi 1l]

Hello!
Primarily, let's decipher how a calorimeter works. In a calorimeter, there is a reaction vessel. Surrounding the vessel is water. We know the temperature and volume of the water. A thermometer is fixed in order to measure the temperature change while a stirrer is implemented to ensure that water is equally distributed. A bomb calorimeter is insulated, meaning that matter cannot be exchanged with surroundings, keeping a constant volume since it is sealed. To add onto the response above, calorimeters must be calibrated. In order to do so, we must find the heat capacity of the calorimeter. This would consist of conducting a reaction where the enthalpy is known and then using the relationship qp=c(deltaT) to find the heat capacity of the entire calorimeter. When the heat capacity and heat transferred of the calorimeter is known, we can use the relationship. qsystem+qsurr=0 in order to solve of the specific heat capacity of the reaction, given that temperature change and mass is given.