Why is heat capacity different for different materials?

Sep 25, 2015

Because $1 g$ of one substance does not contain the same number of atoms in another substance.

Explanation:

Specific heat capacity by definition is the amount of energy needed to raise the temperature of $1 g$ of a substance by one degree.

Raising the temperature of a substance means changing the average kinetic energy of its particles.

Since all substances are made from different particles (atoms) that have different masses, therefore, $1 g$ of one substance will not contain the same number of particles in $1 g$ of another substance.

For example, the molar mass of copper is 63.55 g/mol and the molar mass of sulfur is 32.07 g/mol, therefore, in $1 g$ of sulfur there will be twice as many atoms as in $1 g$ of copper, and therefore, the specific heat capacity of sulfur will be higher (0.73 J/(g.""^@C) than the specific heat capacity of copper (0.385 J/(g.""^@C).