You have two pots of water sitting on a stove. In one, the water is moving about, tumbling, and bubbling. In the other, the water is still. Which is boiling? From common experience we know that as we heat water it begins to move, tumble, and bubble; this is the state we commonly call boiling. This familiar observation lies at the heart of understanding temperature and heat. Temperature is a measure of the average kinetic energy of atoms and molecules in a substance (Ostdiek and Bord 2018, 170).
