Chemical Reactions

2. the tiny pieces that all matter—all the stuff in the world—is made of
4. an object, diagram, or computer program that helps us understand something by making it simpler or easier to see
6. a group of atoms joined together in a particular way
7. the relative size of things
8. able to cause damage
9. something that is made of all the same atoms or groups of atoms
12. to change the order or position of something
13. a process in which atoms rearrange to form new substances
14. the temperature at which a substance changes from the solid phase to the liquid phase
15. a substance that is added to soil to help plants grow

1. a structure formed by repeating groups of atoms that link together in a large network
3. an ending substance that is made during a chemical reaction
5. a starting substance that is part of a chemical reaction
10. the temperature at which a substance changes from the liquid phase to the gas phase
11. something that can be observed about a substance, such as color, smell, or boiling point
13. letters and numbers showing the types and number of atoms that repeat to make up a substance