Pick out the wrong statement.

• Atomic heat capacities of the crystalline solid elements are nearly constant and equal to 6.2 kcal/kg-atom according to the law of Petit and Dulong.
• Atomic heat capacities of all solid elements decrease greatly with decrease in temperature, approaching a value of zero at absolute zero temperature, when in the crystalline state.
• Generally, the heat capacities of compounds are lower in the liquid than in the solid state.
• The heat capacity of a heterogeneous mixture is an additive property, but when solutions are formed, this additive property may no longer exist.