Chemical

3. Matter can enter from or escape to the surroundings
6. The process when two or more elements or compounds combine to make a more complex substance
12. The process that breaks down compounds into simpler products
13. The substances that you have in the beginning
15. Characteristic of a substance that describes its ability to change into other substances
16. A reaction that releases energy in the form of heat
17. A solid that forms from solution during a chemical reaction
18. A short and easy way to show a chemical reaction using symbols instead of words
19. The study of matter and how matter changes

1. Matter is not allowed to enter or leave
2. A principle that states that during a chemical reaction, matter is not created nor destroyed
4. Anything that has mass and takes up space
5. A reaction in which energy is absorbed
7. A number placed in front of a chemical formula in an equation
8. A change in matter that produces one or more new substances
9. A rapid reaction between oxygen and fuel
10. Any change that alters the form or appearance of a substance but does not make a substance into another substance
11. When the reaction is complete, you have new substances
14. When one element replaces another in a compound or when two elements in different compounds trade places