Question

the following particle diagram represents the heating of solid gallium at its melting point. which of the following statements best explains the difference in the arrangement of particles before and after heating? a when the gallium is heated, the particles increase in size and take up more space. b when the gallium is heated, it changes from a compound to individual atoms that can move away from each other. c when the gallium is heated, the motion of the particles increases, so the particles can partially overcome the attractive forces between them. d when the gallium is heated, the motion of the particles increases and there are

Explanation:

• Option A: Particles do not increase in size during phase change. Heating causes change in particle motion, not size.
• Option B: Gallium is an element (not a compound). It does not change from a compound to atoms.
• Option C: When heated at melting point, particle motion increases. In solid, particles have fixed positions. In liquid (after melting), particles can move more freely as they partially overcome attractive forces.
• Option D: The statement is incomplete.

Answer:

C. When the gallium is heated, the motion of the particles increases, so the particles can partially overcome the attractive forces between them.