Fill in the following blanks with suitable words :
Melting of wax is a _____ change but burning of wax is a _____change.

Answer

To fill in the blanks in the given question, we need to analyze the two processes: melting of wax and burning of wax.

1. **Understanding Melting of Wax**:
- When wax is heated, it changes from a solid to a liquid state. This process is known as melting.
- During melting, the chemical composition of the wax remains the same; it only changes its physical state from solid to liquid.
- Since there is no new substance formed and the change can be reversed (the wax can solidify again), this is classified as a **physical change**.

2. **Understanding Burning of Wax**:
- When wax is burned, it undergoes a chemical reaction. The wax reacts with oxygen in the air, producing carbon dioxide and water vapor as byproducts.
- In this process, new substances are formed (carbon dioxide and water), and the original wax cannot be recovered.
- Since new substances are created and the change cannot be reversed, this is classified as a **chemical change**.

Now, we can fill in the blanks:

**Melting of wax is a** **physical** **change but burning of wax is a** **chemical** **change.**

### Final Answer:
Melting of wax is a **physical** change but burning of wax is a **chemical** change.