During the melting of ice at 0°C, the temperature remains constant because the heat supplied is used to: MCQ with Answer and Explanation

During the melting of ice at 0°C, the temperature remains constant because the heat supplied is used to:
A. Break intermolecular bonds
B. Increase kinetic energy of molecules
C. Increase potential energy only
D. Both (b) and (c)
Answer: Option D
Solution (By JKExamLibrary)
During phase change (melting), heat energy (latent heat) is used to overcome intermolecular forces, increasing potential energy while kinetic energy (hence temperature) remains constant. Temperature reflects average kinetic energy; since it doesn't change, kinetic energy is unchanged. The energy breaks hydrogen bonds in ice, allowing molecules to move freely in liquid. Memory tip: 'Latent heat changes state, not temperature'. This conceptual question tests understanding of microscopic interpretation of phase changes, frequently examined in competitive tests to assess depth beyond formula recall.

This question belongs to: Science Physics

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