Why can gases and liquids both transmit heat by convection?

A. Their particles are free to move away from each other.

B. They both have fixed volume.

C. They both contain charged particles.

D. Their particles both vibrate around fixed positions.

A. Their particles are free to move away from each other.

Gases and liquids both transmit heat by convection because their particles are free to move away from each other (option A).

Explanation:

Convection is a process in which heat is transferred between two liquid substances, between two gaseous substances or a gas and a liquid when they are at different temperatures. The heat flux is produced from the body with the highest temperature to the substance with the lowest temperature.

The transmission of heat by convection is based on the actual movement of the molecules of a substance. Both liquids and gases are considered fluids where their particles are free to move away and move from each other. In solids particles vibrate around fixed positions and have a fixed volume.

Gases and liquids both transmit heat by convection because their particles are free to move away from each other (option A).