Question

What happens to water molecules as water is heated?

a. The molecules get closer together.
b. The molecules become less dense.
c. The molecules sink.

Answer 1

As water is heated, the correct understanding of what happens to water molecules includes the following aspects:

- The molecules gain energy and move faster, which causes them to spread apart. This leads to an increase in volume and a decrease in density.
- Therefore, heated water becomes less dense than cooler water, which is why it rises to the top.

Given the options:

a. The molecules get closer together. **(Incorrect)**
b. The molecules become less dense. **(Correct)**
c. The molecules sink. **(Incorrect)**

So, the best answer is **b. The molecules become less dense.**