1. How to tell the difference Physical and Chemical Changes

2. Physical Change Substance may seem different, but the way the atoms link up is the same.

3. Signs of a physical change: If the substance only changes shape, size, or state of matter. Example - Salt dissolves in water but it is still salt and water.

4. It changes phase (freezes, boils, evaporates, condenses) It’s a physical change when...

5. Changes the way the molecules link up Makes new substances Chemical Change

6. Signs of a chemical change: It burns The temperature changes without heating/cooling

7. It’s a chemical change if... It gives off a gas ( can be seen as bubbles)

8. It’s a chemical change if... It forms a precipitate (as a new substance)

9. It might be a chemical change if... The substance changes color. This one is tricky! If you add color to a sheet of paper, you’ve only changed the paper physically. Don’t use this one as sole evidence of a chemical change. A color change can support other evidence, but by itself, does not necessarily indicate a chemical change.

10. What kind of change is it if someone... Tears up paper? Physical change Mixes salt and water? Physical change

11. What kind of change is it if someone... Burns paper? Chemical change Evaporates salt water? Physical change

12. What kind of change is it if someone... Mixes vinegar and baking soda? Chemical change