This area chart shows molar heat capacity - the energy needed to heat one mole of an element by one degree. Unlike specific heat, this measures per-atom rather than per-gram behavior.

The Dulong-Petit law predicts all solid elements should have molar heat capacity around 25 J/(mol·K), and most metals cluster near this value. Deviations reveal quantum effects: light elements (beryllium, boron, carbon) have lower values because their high-frequency atomic vibrations aren't fully excited at room temperature.