Chapter 5 lesson 1

4. The new substances that form.
6. Increases the reaction rate by lowering the activation energy needed.
7. The amount of a substance in a given volume.
9. Substances that undergo the chemical changes.
10. Any change that alters the form or appearance of a substance but does not change it into another substance
13. The energy released as the products form is greater that the energy required to break the bonds of the reactants.
14. Matter can enter from or escape to the surroundings.
15. Matter does not enter or leave
17. A number placed in front of a chemical formula in an equation.
18. During a chemical reaction, matter is not created or destroyed.
20. When two or more elements or compounds combine to make a more complex substance.

1. When one element replaces another element in a compound or if two elements in different compounds trade places.
2. A solid that forms from liquids during a chemical reaction.
3. energy The minimum amount of energy needed to start a chemical reaction.
5. A way to show a chemical reaction, using symbols instead of words.
8. More energy is required to break the bonds of the reactants than is released by the formation of the products.
11. A change in matter that produces one or more new substances.
12. Reaction that occurs when compounds break down into simpler products.
16. A material used to decrease the rate of a chemical reaction.
19. The cells in your body that contain thousands of biological catalysts.