vocab

2. a number that summarizes a set of data and that can be computed by adding all the numbers in a list and then dividing by the number of numbers in the list
4. a measure of how hot or cold something is
7. the moment when two objects hit each other
9. heating unit that stores and warms water
10. a group of atoms joined together in a particular way
12. tiny organisms that are made of a single cell
13. a small part that is meant to show what the whole is like
14. the energy that an object has because it is moving
17. the total kinetic energy of all the molecules that make up a sample
18. the ability to make things move or change

1. water that is underground
3. to make something safe to eat or drink by heating it
5. a balanced state in which a system is stable, such as when two or more samples are at the same temperature
6. when something stays mostly the same over time
8. a set of interacting parts forming a complex whole
11. when something becomes different over time
15. to reach a conclusion using evidence and reasoning
16. anything that has mass and takes up space
17. to move from one object to another or one place to another