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Matter in Our Surroundings — Science STD 9 — Question

CBSE BoardEnglish MediumSTD 9ScienceMatter in Our Surroundings1 Mark
MCQ
What happens when a solid melts:
  • A
    Its molecules move faster
  • B
    Its molecules move closer together
  • C
    The movement of its molecules decreases
  • D
    The temperature decreases although heat is added
✓

Answer

  1. Its molecules move faster

Explanation:

Solid-state has the least intermolecular space and most packed structure.

On heating of a solid, the intermolecular forces decrease, space between the molecules increases.

The particles gain energy and there is an increase in kinetic energy and the molecules move faster.

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