ΔH can be determined experimentally by measuring the magnitude of the ΔT the heat flow produces.
The measure of heat flow is called calorimetry.
The device used to measure heat flow is a calorimeter.
All substances change temperature when they are heated, but the magnitude of the temperature change produced by a given quantity of heat varies from substance to substance.
The heat capacity, C of an object is the amount of heat required to raise its temperature by 1 K (1 oC). The greater the heat capacity, the greater the heat required to produce a given increase in temperature.
The heat capacity of one mole of a substance is called its molar heat capacity, Cmolar.
The heat capacity of one gram of a substance is called its specific heat capacity, s - or simply specific heat, represented by the equation:
For heat calculations, the equation can be rearranged to:
- s = specific heat capacity
- m = mass, in grams
- q = heat, in Joules
- ΔT = temperature change, either K or oC
q = s X m X ΔT