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5. Using soil, cover all areas that might allow air to enter.

6. Wait for the burning to continue overnight, then uncover.

7. Observe what has happened.
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Questions

1. Explain the difference between the results in Experiments

2 and 3.

2. What caused different results in these experiments?

Results

When firewood is burnt under a metal container, the limited
supply of oxygen causes the materials to burn incompletely.
Upon uncovering the set up the next day, it is observed that

the firewood has not fully combusted, indicating incomplete
combustion. Charcoal making is an example of incomplete
combustion; when wood burns in a pit covered with soil, it turns
into charcoal due to the limited oxygen supply.

Conclusion

The experiment demonstrated incomplete combustion caused
by insufficient oxygen, resulting in unburnt charcoal. In this
experiment, burning firewood in a limited amount of oxygen

often releases heat without light. The firewood changed into
charcoal due to the absence of enough oxygen gas.

Effects of combustion

The combustion process can affect living organisms and the
environment. These effects can be good or bad.

Advantages of combustion
The following are some of the benefits of the combustion

process:

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