Question

Why would you subtract the heat of a calorimeter when calculating heat of the reaction? hint: the heat of the calorimeter is the amount of heat that the calorimeter absorbs from the solution-each calorimeter will absorb a certain amount of heat, which means that the temperature change that you measure is actually less that the ideal temperature change.

Answer 1

you mean subtract product from reactant or subtract what ??

Answer 2

Oh sorry I made a typo. Why would you subtract the heat capacity of the calorimeter when calculating the heat of reaction

Answer 3

Dela T = T final - T initial.
T final is bigger then it gain energy(take heat),so you have to put -ve sign to get - value which means taking.
T final is smaller then it lose energy (deliver heat), so you have to put - sign to get + value which means producing.
The negative sign indicates that the calorimeter is gaining energy and the water in the calorimeter is losing energy.
http://www.physicsclassroom.com/class/thermalP/Lesson-2/Calorimeters-and-Calorimetry

Answer 4

Ok i got it thanks a lot!

Answer 5

you are welcome.
that minus sign don't call it subtract ( i imagined that you will subtract it from the product).