Chemical Reactions

3. letters and numbers showing the types and number of atoms that repeat to make up a substance
5. an ending substance that is made during a chemical reaction
7. the tiny pieces that all matter—all the stuff in the world—is made of
8. a process in which atoms rearrange to form new substances
10. able to cause damage
11. something that is made of all the same atoms or groups of atoms
12. a substance that is added to soil to help plants grow
15. to change the order or position of something
16. the temperature at which a substance changes from the liquid phase to the gas phase

1. an object, diagram, or computer program that helps us understand something by making it simpler or easier to see
2. the relative size of things
4. a structure formed by repeating groups of atoms that link together in a large network
6. the temperature at which a substance changes from the solid phase to the liquid phase
9. a group of atoms joined together in a particular way
13. a starting substance that is part of a chemical reaction
14. something that can be observed about a substance, such as color, smell, or boiling point