Heat Capacity

Heat Capacity
When a substance is heated, its change in temperature(∆T) is proportional to the quantity of heat energy it absorbs(q), thus:

q/∆T = constant

The value of this constant is different for each substance and is called that substance's 'heat capacity'.

Specific Heat Capacity
The specific heat capacity(c) of a substance is the amount of heat energy required to raise 1 gram of that substance by 1 degree kelvin.

c = q/(mass * ∆T)

Molar Heat Capacity
The molar heat capacity(C) of a substance is the amount of heat energy required to raise the temperature of 1 mole of that substance by 1 degree kelvin.

C = q/(moles * ∆T)

Units
Heat energy is in joules, temperature is in degrees kelvin, and mass is in grams, thus c has units of J/(K*g) and C has units of J/(K*mol).