All particles have energy, and the energy varies depending on the temperature the sample of matter is in, which determines if the substance is a solid, liquid, or gas. Solid particles have the least amount of energy, and gas particles have the greatest amount of energy.There are spaces between particles of matter. The average amount of empty space between molecules gets progressively larger as a sample of matter moves from the solid to the liquid and gas phases.

Solids: Particles are held together in a regular lattice and can only vibrate on their mean position. Inter particular forces of attraction are strong.
Liquids: Can move or slide past each other however still close together. Inter particular forces of attraction are weaker
Gases: Particles far apart and can move rapidly and freely. When collide move of in all directions. Inter particular forces of attraction are negligible.

Gases have the greatest energy as they need it to break away from forces of attraction and move at a greater rate. Solids have the least as all they can do is vibrate on mean position.