The science of burning

This task is about what is needed for burning to happen.

flames of fire

Imagine what our lives would be like without fire.
Fire brings us many benefits.
However, it is also very dangerous.
To make good decisions about managing fire we need to know a bit about the science of burning.

Question 1Change answer

What are the three things that are needed for a fire to burn?

1 2 3
the fire triangle
To check your answers, look at the fire triangle, which shows the three things needed for a fire to burn.  
If any are missing, burning will not take place.
Thinking about your answers
 

Fuel is the best answer.

Did you give an example of something, e.g., wood, coal, trees, natural gas, petrol, etc.?

Fuel is a better word to use because it covers all of these. Anything that will burn is a fuel. A fuel has stored energy that is released during burning mostly as heat and light.

Oxygen is the best answer.

Was air your answer?

Oxygen is a better answer. It is the particular gas in air that is needed for burning to continue. (This is a bit like our breathing. We breathe air, but it is the oxygen in the air that we need.)

Heat is the best answer.

Was your answer matches or a lighter?

Heat is a better answer because it covers anything that heats up the fuel enough to set it on fire. (It is the flame or spark from the match or lighter that ignites the fuel.)
The next four questions check how well you understand  the fire triangle in real life situations. 

Question

When making a hangi, wood is burnt in a pit in the ground to heat stones.
Which is the fuel for the fire?

    • Air

    • Stones

    • Wood

    • Dirt

Question

A  barbecue stops going when the gas in the gas bottle runs out.
Why does this happen?

    • There is no more oxygen.

    • There is no heat to set it alight.

    • There is no fuel.

Question

In very dry conditions, why is it dangerous to throw a  lighted cigarette butt out of a car window?

    • It provides a heat source.

    • It provides oxygen.

    • It provides fuel.

Question

If a pan of fat catches fire, one way to stop the fire is to put the lid on the pan. 

How does this stop the fat burning?

    • It removes the heat source.

    • It removes oxygen.

    • It removes fuel.