Question

Roads often have to be repaved because they crack over time. Sometimes this cracking is due to the fact that the roads (as well as other objects) have a tendency to expand when heated and contract when cooled. Thermal expansion and contraction are examples of
A.
physical and chemical changes.
B.
physical changes.
C.
chemical changes.
D.
neither physical nor chemical changes.

Answer 1

B. Physical Change - The molecules do not change shape or size. They do not contract or expand only.