Which phase a substance is in depends on the balance between its intermolecular forces and its molecules':

1. Intermolecular forces hold particles close together. 2. The particles' kinetic energy provides the energy required to overcome those forces and increase the distance between particles. 3. The phase in which a substance exists depends on the relative extents of its intermolecular forces and the kinetic energies of its molecules. 4. Cooling or compressing tips that balance toward the solid. _Source: OpenStax Chemistry 2e (CC BY 4.0), Ch 10 'Liquids and Solids', sections 10.1-10.6_