1. Describe the ways that burning changes the nature of wood.

2. A substance always has _______ properties, even though they are difficult to observe.

3. Scientists use __________ properties to help them identify and clasify matter.

4. How do you know that baking a cake involves chemical changes?

5. List some signs or clues that show that a change you are observing is a chemical change.

6. Because ______________________ change the identity of the substances involved, they are hard to reverse.

7. How could some chemical changes be reversed? Give and example.

8. During _______ , the composition of a substance does not change.

Identify wheter the following changes are physical changes or chemical changes.

9. Mising vinegar and baking soda

10. Grinding baking soda into a powder.

11. Souring Milk