Basic Concepts
In a nutshell: Chemical changes make new substances with different properties.
## Discovering Chemical Changes
Chemical changes create new substances with different properties. The molecules are rearranged, and you might see color changes, gas bubbles, or even heat and light being released.
### Signs of Chemical Changes
- Color change (like apple slices turning brown)
- Formation of gas (bubbles when vinegar and baking soda mix)
- Release of energy (light, heat, or sound)
- Formation of a solid (precipitate)
## Chemical Changes in Everyday Life
Chemical changes are everywhere! Cooking, rusting, burning, and even digesting food in your body involve chemical changes.
### Can Chemical Changes Be Reversed?
Most chemical changes are not easily reversible. Once wood burns to ash, it can't turn back into wood!
## Why Study Chemical Changes?
Knowing about chemical changes helps us cook safely, prevent rust, and even develop new materials.
Examples
- Cooking an egg until it solidifies.
- Iron nails rusting when left outside.
Key terms
- Chemical Change
- A change that forms new substances with different properties.
- Reaction
- The process where substances interact to form new substances.