Burning napkin

You know, cotton pretends to be a bit lazy when it comes to burning. It needs a high temperature, roughly between 300 and 400°C, before it catches fire. But alcohols are much quicker to catch fire. They are like the superheroes of combustibles, as they can already catch fire at very low temperatures. For pure ethanol, a type of alcohol, it is only 12°C!

So, if we want something to burn, we use the clever trick of mixing alcohol and water. Water is like a cool friend that protects the flammable cloth in two ways:

1. Water can absorb a lot of heat before it gets hot itself. So, when the mix of alcohol and water starts to burn, the water soaks up all that heat.

2. Some of the water also turns into water vapour due to the heat. And did you know that when water evaporates, it actually takes heat from its surroundings? That means it also helps keep the cloth cool, just as your body cools when you sweat and that sweat evaporates from your skin.

So, thanks to the water, the cotton cloth stays nice and cool even if it gets near fire. Clever, isn't it?