Across
- 5. A number in front of a chemical formula in an equation that indicates how many molecules or atoms of each reactant and product are involved in a reaction
- 7. A type of protein that spreads up a chemical reaction in a living thing a biological catalyst
- 8. The amount of one material in a certain volume of another material
- 10. A reaction in which one element replaces another in a compound or when two elements in different compounds trade places
- 12. reaction, A reaction that absorbs energy
- 14. A Substance that enters into a chemical reaction
- 15. energy, The minimum amount of energy needed to start a chemical reaction
- 17. change, A change that alters the form or appearance of material but does not make the material into another substance
- 20. system, A system in which no matter is allowed to enter or leave
Down
- 1. a material that decreases the rate of a reaction
- 2. A solid that forms a solution during a chemical reaction
- 3. A chemical reaction in which two or more simple substances combine to form a new more complex substances
- 4. change, A change in which one or more substances combine or break apart to new substance.
- 6. A chemical reaction that breaks down compounds into simpler products
- 9. A substance formed as a result of a chemical reaction
- 11. reaction, A reaction that releases energy usually in the form of heat
- 13. conservation mass, the principle that the total amount of matter is neither created nor destroyed during any chemical or physical change
- 16. A solid in which the atoms arranged in a pattern that repeats again and again
- 18. equation, A short easy way shows a chemical reaction using symbols.
- 19. system, A system in which can enter from or escape to the surroundings