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Question
What is meant by latent heat? How will the state of matter transform if latent heat is given off?
Solution
- The heat energy required to change substance from one state to another at constant temperature is called as latent heat of a substance.
- When latent heat is given off from a substance, it causes the strengthening of the bonds between atoms or molecules causing a change of state of the substance.
- When a liquid substance gives off latent heat of fusion, strengthening of bonds results into pulling of atoms or molecules of liquid closer and eventually it changes into solid-state.
- Similarly, when a gaseous substance gives off latent heat of vaporisation, strengthening of bonds results into the pulling of atoms or molecules of gas closer and eventually it changes into a liquid state.
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