The burning of candle is a ___________ change.

Options

A. Periodic and irreversible
B. Reversible and chemical
C. Non-periodic and reversible
D. Chemical and irreversible

Explanation

To solve the question "The burning of candle is a ___________ change," we can follow these steps:

### Step 1: Understand the Process of Burning
When a candle burns, it undergoes a process where the wax (the main component of the candle) reacts with oxygen in the air. This reaction produces heat, light, carbon dioxide, and water vapor.

**Hint:** Think about what happens to the candle when it burns. Does it change into something else?

### Step 2: Identify the Type of Change
The burning of a candle involves a chemical reaction. During this reaction, the chemical composition of the wax changes as it transforms into different substances (like carbon dioxide and water).

**Hint:** Consider whether the original material (the wax) can be recovered after the candle has burned.

### Step 3: Determine if the Change is Reversible or Irreversible
A key characteristic of a chemical change is that it is usually irreversible. Once the candle wax has burned and turned into gases and other products, you cannot revert those products back into the original wax.

**Hint:** Ask yourself if you can turn the products of burning back into the candle wax.

### Step 4: Conclude the Answer
Based on the understanding that burning a candle is a chemical change and that it is irreversible, we can conclude that the burning of a candle is a **chemical change**.

**Final Answer:** The burning of candle is a **chemical** change.

### Summary of Steps:
1. Understand the burning process.
2. Identify it as a chemical change.
3. Determine it is irreversible.
4. Conclude the answer.