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Why does steam release so much thermal energy when it condenses?

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Logs burning in a fireplace with bright flames. — heat What's the relationship between heat and temperature?

Steam releases a significant amount of thermal energy during condensation because of its high latent heat of vaporization.12

When liquid water is converted into steam, a large amount of energy is required to break the strong hydrogen bonds between water molecules and overcome the forces of attraction that hold the liquid together. This energy is stored within the steam as latent heat—energy associated with a phase change that occurs without a change in temperature.123

When steam condenses back into a liquid, this stored energy is released. Because the heat of vaporization for water is exceptionally large—approximately 2,260 kilojoules per kilogram at standard atmospheric pressure—steam acts as a highly effective medium for transporting and releasing thermal energy in industrial processes and heat engines.1425