Heat is molecular motion. All substances are made up of tiny molecules which are

in a state of rapid motion. As the temperature of a substance is increased the motion increases and as the temperature decreases, the molecular motion decreases.

If all heat is extracted (absolute zero) from a substance, the molecular motion will cease completely. Heat always flows from a warm substance to a cooler substance; that is from higher temperatures to lower temperatures. Faster moving molecules impart some of their energy to slower-moving molecules.

Therefore, the faster molecule slows a little and the slower one moves a little faster. Sometimes, however, the molecules instead of moving slower or faster, change their shape. The change in shape is caused by one or more of the atoms in the molecules shifting to a different position and this shift in the atomic structure of the molecule may cause it to change from a gas to a liquid or vice versa.

Heat is molecular motion. All substances are made up of tiny molecules which are in a state of rapid motion. As the temperature of a substance is increased the motion increases and as the temperature decreases, the molecular motion decreases. If all heat is extracted (absolute zero) from a substance, the molecular motion will cease completely. Heat always flows from a warm substance to a cooler substance; that is from higher temperatures to lower temperatures. Faster moving molecules impart some of their energy to slower-moving molecules. Therefore, the faster molecule slows a little and the slower one moves a little… Heat and Heat Flow Heat and Heat Flow User Rating: Be the first one !