The specific heat of water is 4200 J kg -1 ° C -1 or 1 cal g -1 C -1 , which high compared with most other substances .
Gases have two types of specific heat 1 . The specific heat capacity at constant volume ( Cv ). 2 . The specific heat capacity at constant pressure ( Cr ).
Specific heat at constant pressure ( Cp ) is greater than specific heat constant volume ( CV ), i . e ., Cp > CV .
For molar specific heats Cp – CV = R where R = gas constant and this relation is called Mayer ’ s formula .
The ratio of two principal sepecific heats of a gas is represented by γ .
The value of y depends on atomicity of the gas .
Amount of heat energy required to change the temperature of any substance is given by
Q = mcΔt where , m = mass of the substance , c = specific heat of the substance and Δt = change in temperature . Thermal ( Heat ) Capacity
Heat capacity of any body is equal to the amount of heat energy required to increase its temperature through 1 ° C .
Heat capacity = me
where c = specific heat of the substance of the body and m = mass of the body .
Its SI unit is joule / kelvin ( J / K ).