Combustion is a reaction between a substance and oxygen that releases heat and light energy. A fuel is a substance that combusts to release useful energy. Many fuels are hydrocarbons obtained from crude oil that burn easily and release a large amount of energy. The complete combustion of hydrocarbons produces carbon dioxide and water.

1. Combustion, fuels and hydrocarbons
When a substance burns,
it is said to combust.
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2. Combustion, fuels and hydrocarbons
When a substance burns,
it is said to combust.
Combustion is a rapid
reaction between a
substance and oxygen
that releases heat and
light energy.
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3. Combustion, fuels and hydrocarbons
When a substance burns,
it is said to combust.
Combustion is a rapid
reaction between a
substance and oxygen
that releases heat and
light energy.
A fuel is a substance that reacts with oxygen (combusts) to
release useful energy.
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4. Combustion, fuels and hydrocarbons
When a substance burns,
it is said to combust.
Combustion is a rapid
reaction between a
substance and oxygen
that releases heat and
light energy.
A fuel is a substance that reacts with oxygen (combusts) to
release useful energy.
Many fractions obtained from crude oil are used as fuels
because they contain hydrocarbons that burn easily and
release a large amount of useful energy.
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5. Complete combustion of hydrocarbons
Plenty of air is needed to provide enough oxygen for a
hydrocarbon fuel to burn completely.
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6. Complete combustion of hydrocarbons
Plenty of air is needed to provide enough oxygen for a
hydrocarbon fuel to burn completely.
The blue flame of a gas hob
or a Bunsen burner is an
example of complete
combustion of a hydrocarbon
(in this case, natural gas).
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7. Complete combustion of hydrocarbons
Plenty of air is needed to provide enough oxygen for a
hydrocarbon fuel to burn completely.
The blue flame of a gas hob
or a Bunsen burner is an
example of complete
combustion of a hydrocarbon
(in this case, natural gas).
What are the products of the
complete combustion of a hydrocarbon?
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8. Complete combustion of hydrocarbons
Plenty of air is needed to provide enough oxygen for a
hydrocarbon fuel to burn completely.
The blue flame of a gas hob
or a Bunsen burner is an
example of complete
combustion of a hydrocarbon
(in this case, natural gas).
What are the products of the
complete combustion of a hydrocarbon?
carbon
hydrocarbon + oxygen  + water
dioxide
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9. Complete combustion of propane
Propane is a hydrocarbon used in camping gas. What is the
equation for its combustion?
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10. Complete combustion of propane
Propane is a hydrocarbon used in camping gas. What is the
equation for its combustion?
carbon
propane + oxygen  + water
dioxide
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11. Complete combustion of propane
Propane is a hydrocarbon used in camping gas. What is the
equation for its combustion?
carbon
propane + oxygen  + water
dioxide
C3H8 + 5O2  3CO2 + 4H20
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12. Complete combustion of propane
Propane is a hydrocarbon used in camping gas. What is the
equation for its combustion?
carbon
propane + oxygen  + water
dioxide
C3H8 + 5O2  3CO2 + 4H20
How would the equations change if butane was used?
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