Solid molecular structure

In the solid state of matter, the particles that make up a substance are closely packed together and held in a fixed position by strong intermolecular forces, such as electrostatic attraction, hydrogen bonding, or covalent bonding.

Kinetic energy

All matter is made up of tiny particles that are in constant motion. Kinetic energy refers to the energy that the particles (atoms, ions, or molecules) have because they are moving.

Thermal energy

The temperature of matter is related to the average kinetic energy of its particles. When matter is heated, the particles gain energy and move faster, resulting in an increase in temperature.