Chemical
Reactions
Reactions
Which experiment did we do this week that was a chemical reaction?
Elephant's toothpaste
Which activity this week was a physical change?
Yarn Ornaments
Melting butter... is it Physical or Chemical?
Physical. The butter changes from a solid to a liquid, but it is still butter.
What are two clues that showed elephant's toothpaste was a chemical reaction?
Optional Answers:
1. It got warm.
2. It produced foam.
3. A new product formed.
When done correctly, what should the yarn have done?
Changed its shape.
Toasting Bread... is it Physical or Chemical?
Chemical. Heating the bread creates new substances, so it cannot be changed back into plain bread.
During elephant's toothpaste, a gas was released.
What did I say was the gas that helped make all the foam?
Hint: It's in the air.
Oxygen gas
Besides yarn ornaments, what's another example of a physical change?
Here are some examples!
A Rusting Bike... is it Physical or Chemical?
Chemical. The metal in the bike reacts with oxygen to form rust, which is a new substance.