List Four Chemical reactions

Baking soda and vinegar

explosions

rust

fireworks

You should know that chemical reactions are things that you can not change back.

Physical reactions like ripping paper is still physical, the "paper" has not really changed

1) baking soda and vinegar mixed together.

2) An oven cooking a pie.

3) Burning a sheet of paper

4) rust, old peeling of some kind.