Eli5 – does boiling water work as efficiently to put out a fire as cold water or even room temp water?

Question

Or does the molecular structure change in a certain way once heated, and in turn can steam put out a fire.

In: Chemistry

Answer 1

The primary way that water puts out fire is by absorbing the heat energy of the fire. Water has something called a high specific heat capacity. That means it takes a lot of energy to heat up water.

Since things tend towards temperature equilibrium, this means that the water will end up absorbing most of the heat energy out of the system.

So why does boiling water work? Well, boiling water is trying to turn into steam. That phase transition, from a liquid to a gas, is really hard, and takes a *lot* of energy. It takes more energy to actually perform that phase transition for water than it does to bring it up to that boiling point. That means that it still has a LOT of ability to absorb energy out of the system.