Why water extinguishes fire

Have you ever wondered: why does water extinguish a fire? And the answer suggests itself - because it is wet! In fact this is not true. Indeed, many liquids, on the contrary, are not able to extinguish the flame, but to kindle it even more. Take at least alcohol, gasoline or oil.

Water is a special substance with unique properties, among which is the highest heat capacity among liquids. But the most interesting thing is that the heat capacity of water decreases at temperatures from 0 to 37 degrees, and increases again with further heating.

It is thanks to these properties that water is one of the best means for fighting fire. In contact with the flame, it instantly turns into steam, taking away a large amount of heat from the burning object.

The transition of boiling water to water vapor requires five times more energy than heating cold water to 100 degrees.

In addition to direct heat removal, water also extinguishes the flame indirectly. The water vapor generated on contact with fire envelops the burning body, preventing the flow of oxygen, without which combustion is impossible.

This is, at first glance, a paradoxical phenomenon: hot water extinguishes fire faster than cold water. The fact is that the heated water is more likely to turn into steam, which means it will cut off the flow of air to the burning object.

A natural question arises: why do not firefighters extinguish the fire using boiling water? Unfortunately this is not possible.

Modern fire pumps are adapted for pumping extremely cold water, if you replace it with boiling water, under the piston instead of rarefied gas there will be saturated steam under a pressure of 1 atm, and the water will stop rising.

An even more unexpected way of extinguishing a fire is mixing gunpowder with water. Everything is natural: when ignited, the gunpowder quickly burns with the release of a large amount of non-combustible gas, which also cuts off the access of oxygen.

Water is one of the best means for extinguishing a fire, but in no case should you flood burning electrical appliances with water, because water perfectly conducts not only heat, but also electric current.

A person trying to extinguish a burning wire with water may just as well grab a bare live wire with his hands.