When water is poured over burning wood, the fire goes off. This is because

Options

A. temperature of wood decreases
B. temperature of water goes up
C. molecules of water react with oxygen present in the flame
D. the flame vapourises

Answer

**Step-by-Step Solution:**

1. **Understanding the Situation**: When water is poured over burning wood, the fire goes out. This indicates that there is a change in the conditions that allow the fire to continue burning.

2. **Identifying the Key Concept**: The key concept here is the ignition temperature. The ignition temperature is defined as the minimum temperature at which a substance starts to burn.

3. **Effect of Water on Temperature**: When water is poured on burning wood, it cools the wood down. The water absorbs heat from the burning wood, which causes the temperature of the wood to decrease.

4. **Reaching Below Ignition Temperature**: If the temperature of the wood falls below its ignition temperature, it can no longer sustain combustion. Therefore, the fire goes out.

5. **Conclusion**: The primary reason the fire goes out when water is poured over burning wood is that the temperature of the wood decreases below its ignition temperature.

**Final Answer**: The fire goes off because the temperature of the wood decreases below its ignition temperature.

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