Define the following: Chemical change, Reversible change, Periodic change physical change

Explanation

### Step-by-Step Text Solution

1. **Chemical Change**:
- A chemical change is a process where a substance undergoes a transformation that alters its chemical properties. During this change, new substances are formed that have different chemical compositions than the original substance.
- **Example**: Rusting of iron is a common example of a chemical change. When iron reacts with oxygen in the presence of moisture, it forms iron oxide (rust), which is a new substance.

2. **Reversible Change**:
- A reversible change is a type of change that can be undone or reversed. This means that the original substance can be recovered after the change has occurred.
...