A cook places a pot of water over a flame on a stove. What will happen to the water molecules near the surface of the water?

Question

a. They will become more dense and sink.
b. They will become less dense and sink
c. They will become more dense and rise.
d. They will become less dense and rise.

Answer 1

d. They will become less dense and rise.

As the pot of water heats up, the water molecules near the surface gain energy and move faster. This increased energy causes the water molecules to spread apart, which decreases their density. As a result, the less dense water at the surface will rise, while the denser, cooler water will sink. This process contributes to the convection currents in the pot of water.