Question

4 ash measured the temperature of a pond near his house. before he left for school, the water in the pond was 18°c. when he came home from school, the temperature of the pond was higher than it was in the morning. what happened to the water molecules while he was at school?
a) the molecules got closer together.
b) the molecules started moving faster.
c) the water lost cold molecules.
d) the molecules became larger.

Explanation:

Temperature is a measure of the average kinetic energy of molecules. When water temperature rises, the kinetic energy of its molecules increases, meaning they move faster. Molecules getting closer happens when temperature drops (contraction), "cold molecules" do not exist as a distinct type, and molecules do not change size with temperature changes.

Answer:

B. The molecules started moving faster.