States of Matter: Basics

Explore solid, liquid, and gas at the molecular level

Matter exists in solid, liquid, and gas phases depending on temperature and pressure. In a solid, molecules vibrate around fixed positions; in a liquid, they flow past each other; in a gas, they move freely. Phase transitions require energy (latent heat) without temperature change — energy breaks intermolecular bonds. The kinetic energy of molecules is proportional to absolute temperature (KE = 3/2 k_B T).