Answer:
- Bubbles were produced when iron was placed in acid.
- Two liquids were combined, and a solid appeared.
- A white substance turns blue when water was added.
Explanation:
A chemical change can be identified when the original substance changes to a different one.
The following cases are chemical changes:
- Bubbles were produced when iron was placed in acid, because the bubbles represent that a gaseous substance was formed.
- Two liquids were combined, and a solid appeared, because the solid is a new substance that precipitated.
- A white substance turns blue when water was added, because the color change means a new substance was formed.
