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Fire

Fire

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Which component of air is needed in order for fires to burn?

Fire

Do you really need sticks to make a fire? There are other things that can burn. Like plastic. Yes, and old car tires. But then the fish will taste like burnt rubber.

Why... doesn't it... Catch... Fire!? I'm hungry.

Ah, the paraffin stove! Let's pour some paraffin on the wood. Do you really think that's safe? YIKES! - What happened? You were lucky just now, Michael.

Terrible accidents have occurred when people have tried lighting fires using alcohol or paraffin. If Leon and Michael want to kick start the fire - without burning down the whole forest - they'd better learn the basics of fire. Let's begin with - the fire triangle. To begin with, you need a combustible material. A lot of things can burn, such as wood, paper, plastic and cloth.

Spirit and paraffin can burn really well. And a fire needs air, or rather the oxygen in the air. Fire is actually a chemical reaction between oxygen and the combustible substance. Then we need to add heat, to start the chemical reaction. When Michael tried to set fire to the sticks, he didn't succeed.

This is because there is water in the wood - which cools the fire. It takes quite a lot of heat to make the water evaporate. What should Michael have done instead? First of all - use the driest sticks possible. In other words: change the properties of the substance.

He could also add some more heat, maybe by burning some paper to get the fire started. Or, use a substance that starts burning at a lower temperature. In alcohol and petroleum, it's the vapors that catch fire. When the molecules in the gas mix with oxygen in the air, they burn extremely fast. Like an explosion.

Gunpowder, dynamite, and some other explosives consist of substances which include oxygen. That means they can explode even without the help of air. The larger the surface area of a substance that is in contact with oxygen, the better the substance burns. That's why it is easier to start a fire with twigs than with thick branches. If you're done with your fish grilling, maybe you should put out the fire?

We can use the fire triangle to make something stop burning as well. Remove one of the three sides - fuel, oxygen or heat - and the fire goes out. If all the firewood is turned into ash, there's no fuel left, and the fire stops burning. But that could take a while. We can also put out the fire by cooling the wood, by dousing it with water.

Or smother the fire with sand and soil. It acts as an insulating layer between the oxygen and the combustible substance. Now I really fancy a cuppa tea. Oh no! We put the fire out!

It's a good thing we have this paraffin stove then. Or maybe you want to go look for some more dry branches?