Lowering the temperature below the flash point:
Lowering the temperature below the flash point of a substance refers to reducing the temperature at which the substance can ignite and sustain a fire. The flash point is the minimum temperature at which a substance can vaporize to form an ignitable mixture in air.
Here is a detailed explanation of the effect of lowering the temperature below the flash point:
1. Extinguishes the fire: When the temperature is lowered below the flash point, it reduces the availability of heat energy required for the combustion process. As a result, the fire cannot be sustained, and it is extinguished.
2. Reduces the volatility: Lowering the temperature decreases the volatility of the substance, which means it becomes less likely to vaporize and form flammable gases. This reduces the risk of fire or explosion.
3. Increases the safety: By lowering the temperature below the flash point, the risk of accidental ignition or fire is significantly reduced. This promotes a safer environment, especially in areas where flammable substances are present.
4. Prevents reignition: Lowering the temperature below the flash point ensures that even if a fire is temporarily extinguished, it is less likely to reignite due to the reduced availability of heat energy.
5. Does not affect the density: Lowering the temperature does not directly affect the density of the substance. Density is a measure of mass per unit volume and is not influenced by changes in temperature alone.
Therefore, the correct answer is B: extinguishes the fire. Lowering the temperature below the flash point reduces the availability of heat energy, making it impossible for the fire to sustain itself.