Which of the following burns without producing a flame ?

Options

A. camphor
B. coke
C. cooking gas
D. kerosene

Answer

To determine which substance burns without producing a flame, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks which of the given substances burns without producing a flame. We need to evaluate each option carefully.

2. **Evaluating Camphor**:
- When camphor is burned, it vaporizes and produces a flame.
- **Conclusion**: Camphor does produce a flame.

3. **Evaluating Coke**:
- When coke is burned, it does not vaporize and instead burns slowly, producing heat without a visible flame.
- **Conclusion**: Coke burns without producing a flame.

4. **Evaluating Cooking Gas (LPG)**:
- Cooking gas, commonly LPG, burns with a blue flame when ignited.
- **Conclusion**: Cooking gas does produce a flame.

5. **Evaluating Kerosene**:
- Kerosene, when burned, also produces a blue flame.
- **Conclusion**: Kerosene does produce a flame.

6. **Final Evaluation**:
- From the analysis, the only substance that burns without producing a flame is **Coke**.

### Answer:
The substance that burns without producing a flame is **Coke**.

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