| A | B |
|---|
| average | data- add all the numbers in a list and then divide by the number of numbers in the list |
| bacteria | tiny organisms that are made of a single cell |
| collision | the moment when two objects hit each other |
| energy | the ability to make things move or change |
| equilibrium | balanced state in which a system is stable, such as when two or more samples are at the same temperature |
| groundwater | water that is underground |
| kinetic energy | the energy that an object has because it is moving |
| matter | anything that has mass and takes up space |
| molecule | agroup of atoms joined together in a particular way |
| pasteurize | to make something safe to eat or drink by heating it |
| sample | a small part that is meant to show what the whole is like |
| stability | when something stays mostly the same over time |
| system | a set of interacting parts forming a complex whole |
| temperature | a measure of how hot or cold something is |
| thermal energy | the total kinetic energy of all the molecules that make up a sample |
| transfer | to move from one object to another or one place to another |
| water heater | a heating unit that stores and warms water |
