When a substance burns in sufficient supply of air, it produces a blue flame and it said to have undergone _____ combustion.

Options

A. Complete
B. Incomplete
C. Partial
D. Full

Answer

To solve the question, we need to identify the type of combustion that occurs when a substance burns in a sufficient supply of air and produces a blue flame.

### Step-by-Step Solution:

1. **Understanding Combustion**: Combustion is a chemical reaction that occurs when a substance reacts with oxygen, releasing energy in the form of heat and light.

2. **Types of Combustion**: There are two main types of combustion:
- **Complete Combustion**: This occurs when there is a sufficient supply of oxygen. It typically produces a blue flame and results in the formation of carbon dioxide and water.
- **Incomplete Combustion**: This occurs when there is a limited supply of oxygen. It produces a yellow or orange flame and can result in the formation of carbon monoxide or soot.

3. **Identifying the Flame Color**: The question specifies that a blue flame is produced. A blue flame indicates that the combustion is complete, as it signifies that the fuel is burning efficiently with enough oxygen.

4. **Conclusion**: Since the question states that the substance burns in a sufficient supply of air and produces a blue flame, we can conclude that it has undergone **complete combustion**.

### Final Answer:
When a substance burns in sufficient supply of air, it produces a blue flame and it is said to have undergone **complete combustion**.