The freezing point of a substance is the temperature at which it changes from a liquid to a solid state. It is the temperature at which the vapor pressure of the solid and the liquid phases are equal and the substances exist in equilibrium. The freezing point is a characteristic property of a substance and can be used to identify and purify it.
Plan and carry out investigations that demonstrate the chemical and physical processes that form rocks and cycle Earth’s materials (e.g., processes of crystallization, heating and cooling, weathering, deformation, and sedimentation).