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How do temperature changes affect the state of matter?

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Bohr model diagram of a hydrogen atom showing a green nucleus labeled H, a single electron orbit, and text with atomic mass 1.008 and electron configuration 1. — atom The Bohr model describes the structure of atoms, in this case hydrogen.

Temperature changes significantly influence the state of matter by altering the kinetic energy of its constituent atoms and molecules. At the microscopic level, temperature is a measure of this average kinetic energy; as temperature increases, particles move more vigorously, and as it decreases, their motion slows.12

When heat is added to a substance, the increased kinetic energy allows particles to overcome the attractive forces holding them together, facilitating transitions between states. For example, heating a solid provides the heat of fusion necessary for it to become a liquid, and further heating provides the heat of vaporization required for the liquid to enter the gaseous state. Conversely, cooling a gas reduces particle speed, allowing attractive forces to coalesce the particles into a liquid and eventually a solid.23

While temperature changes often cause these phase transitions, a substance may also absorb or release energy—known as latent heat—during a phase change without a corresponding change in temperature.32