The water and the fire

Why the water extinguishes the fire? This question is not always able to correctly answer even the people who have studied physics. The reader, we hope, will not complain to us if we will explain briefly, as the water extinguishes the fire.

Why the water extinguishes the fire? This question is not always able to correctly answer even the people who have studied physics

At first glance, this is strange question, it is unlikely too many people ask this question. After all, the answer seems to be obvious the water is wet.

But not all liquids are able to extinguish the flames. Some, on the contrary, contribute to the fact that the fire flares up stronger. For example, such fluids are gasoline and alcohol.

It should be noted that the water has the highest specific heat of any liquids that decreases in the temperature range from 0 to 37 degrees Celsius. On further heating, it increases again.

Therefore, touching the burning subject, the water turns into steam, thus taking away a lot of heat from the burning body. The boiling water to turn to steam, it is necessary five times more heat than the heating the same amount of cold water up to 100 degrees Celsius.

The water vapor occupied the volume by hundreds of times greater than the water itself. Water vapors displace air, which is essential to combustion.

Thus, the hot water quenched the fire faster than cold. But the point here is that the hot water is turned into steam faster than cold, and accordingly pairs will cut off the access of oxygen to the burning object. Then why not firemen extinguish the fire with the help of boiling water? It is simply impossible.

The fire pumps are adapted to pump exclusively cold water. If it will be replaced with boiling water, then under the piston will be saturated steam at a pressure equal to one atmosphere instead of a rarefied gas. The water will not ascend through the hose.

In order to keep the water extinguished the fire with more power, sometimes mixed into it... gunpowder! It may seem incongruous. However, it is quite reasonable. Gunpowder burns quickly, releasing a large amount of non-combustible gases which extinguish the fire.

We must not forget that the water should not be used to extinguish the electrical appliances. This happens due to its ability to conduct an electric current.

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