Question

Why do most materials expand when heated? A. The warmer molecules are packed together, which causes the matter to increase in size. B. Heat takes up more space than cold. C. The molecules spread out, so volume increases.D. When heated, molecules grow in size, so they take up more space.

Answer 1

Answer: The kinetic energy of that material increases and its atoms and molecules move around more. That  means that each atom will take up more space due to its movement so the material will expand.

Explanation:

D Is what I think it is.