An example of a physical change in matter is breaking a glass bottle.
Here's why:
Physical changes alter the form or appearance of a substance, but not its chemical composition. In other words, the substance remains the same substance, even though it may look different.
- Breaking: When you break a glass bottle, you end up with smaller pieces of glass. The glass is still glass (SiO2), just in a different form. The chemical bonds within the glass molecules aren't broken during this process.
Here are some other examples of physical changes:
- Melting: Changing ice (solid water) into liquid water. It's still H2O.
- Freezing: Changing liquid water into ice.
- Condensing: Changing water vapor (gas) into liquid water.
- Crushing: Crushing a can changes its shape, but it's still aluminum.
- Cutting: Cutting a piece of paper results in smaller pieces of paper.
- Bending: Bending a metal rod changes its shape, but it remains the same metal.
| Physical Change | Description | Reversible? (Often) |
|---|---|---|
| Melting | Solid to Liquid | Yes |
| Freezing | Liquid to Solid | Yes |
| Condensing | Gas to Liquid | Yes |
| Breaking | Dividing a substance into smaller pieces | No |
| Crushing | Reducing the size or altering the shape of a substance | No |
| Cutting | Separating a substance into multiple pieces | No |
| Bending | Changing the shape of a substance | No |
It's important to distinguish physical changes from chemical changes, where a new substance is formed (e.g., burning wood, which creates ash, carbon dioxide, and water).
