We discussed earlier some basic principles about the behavior of gases called the kinetic-molecular theory. Among other things, this theory suggests that gas molecules are in constant motion, and the average speed of the individual gas particles is dependent upon temperature – the higher the temperature, the faster the molecules move. It is not just gas particles that are in constant motion. The molecules and ions that make up liquids and solutions are also continually moving in nearly random directions. As a result, molecules and ions in a solution will collide with one another fairly frequently. As with gases, a temperature increase will produce an increase in the average particle speed.
Beth put water on the stove to boil for making rice. While she was waiting for the water to boil she filled her ice cube trays with water and put them in the freezer. When the water on the stove reached a boil she added her rice and removed it from the heat.
When the water reached boiling were the molecules moving faster or staying at a constant speed?