1. S2 Chemistry Materials from the Earth
Fuels and combustion
S2 Chemistry
Materials from the Earth

2. Key Questions What is a fuel? How many examples of fuels can you name?
What do all fuels have in common?
What makes one fuel better than another?

3. Learning outcomes Success criteria
Understand what fuels are.
You can define the term “fuel”.
You can state four examples of substances which are fuels.
Know what is meant by “combustion”.
You can define the term “combustion”.
Know what is meant by an “exothermic reaction”.
You can define the term “exothermic”.
Know the percentage composition of air.
You can name the two gases which make up most of air, including their percentage.
You can name two other gases which are found in air, including a rough percentage.

4. Fuels and combustion
A fuel is “a substance which is burned to release energy”.
“Combustion” is another word for “burning”.
Burning requires oxygen (O2).
Burning is an “exothermic” reaction because it releases heat energy.

5. Challenge You have: Add water to the tub so that it is about ¼ full.
A candle
A plastic tub
A match
A match box
A glass jar
Add water to the tub so that it is about ¼ full.
The challenge is to get the water from the tub into the glass jar without pouring it from the tub
Once there is water in the tub, it is not allowed to move.

7. Air
What is the percentage composition of air?

8. Learning outcomes Success criteria
Understand what fuels are.
You can define the term “fuel”.
You can state four examples of substances which are fuels.
Know what is meant by “combustion”.
You can define the term “combustion”.
Know what is meant by an “exothermic reaction”.
You can define the term “exothermic”.
Know the percentage composition of air.
You can name the two gases which make up most of air, including their percentage.
You can name two other gases which are found in air, including a rough percentage.

9. S2 Chemistry Materials from the Earth
Types of combustion
S2 Chemistry
Materials from the Earth

10. Learning outcomes Success criteria
Understand the difference between complete and incomplete combustion.
You can describe examples of situations where complete and/or incomplete combustion will take place.
You can write word equations for the complete and incomplete combustion of a hydrocarbon.

11. Types of combustion
Look at a Bunsen burner and the different types of flame.
There are 2 types of combustion
complete and incomplete

12. Incomplete combustion
Hydrocarbon +
oxygen
carbon dioxide +
water
Incomplete combustion
Hydrocarbon
oxygen
carbon monoxide
water +
carbon

13. Learning outcomes Success criteria
Understand the difference between complete and incomplete combustion.
You can describe examples of situations where complete and/or incomplete combustion will take place.
You can write word equations for the complete and incomplete combustion of a hydrocarbon.

14. Products of combustion
S2 Chemistry
Materials from the Earth

15. Learning outcomes Success criteria
Know how to predict what products will be produced when a substance is burned.
Given the names of elements in a fuel, you can state what products will be produced.
You can name the products produced given the name of the elements present in a fuel.

16. Testing for the products of combustion
Cobalt chloride paper
Lime water

17. What evidence is there for complete combustion?
What evidence is there for incomplete combustion?
What THREE products does this experiment detect?
What is an acceptable conclusion from this experiment?
Carbon dioxide
Carbon
Carbon dioxide, water and carbon
The candle contains carbon and hydrogen

18. Burning fuels
When a substance burns ALL of the different types of atom in it react with oxygen
Atom in fuel
Products
Carbon
Carbon dioxide, carbon monoxide
Hydrogen
Hydrogen oxide (water)
Sulphur
Sulphur dioxide

19. Equations
Write word and chemical equations for the following substances burning (complete combustion):
Methane (CH4)
Glucose (C6H12O6)
Hydrogen (H2)
Ethanol (C2H5OH)
Carbon
*Coal (contains carbon, hydrogen and sulphur) – no need for a chemical equation here

20. Learning outcomes Success criteria
Know how to predict what products will be produced when a substance is burned.
Given the names of elements in a fuel, you can state what products will be produced.
You can name the products produced given the name of the elements present in a fuel.

21. S2 Chemistry Materials from the Earth
Oxides of carbon
S2 Chemistry
Materials from the Earth

22. Learning outcomes Success criteria
Know characteristic properties of carbon dioxide and carbon monoxide.
You can describe the properties of carbon dioxide and carbon monoxide, including:
State at room temperature
Flammability
You can state why high concentrations of carbon monoxide are dangerous.
You can state the test for carbon dioxide gas, naming the chemical you would use and the result.

23. Carbon Dioxide vs Monoxide
Chemical
Formula
Chemical Test
Other information
Carbon dioxide
CO2
Lime water turns from colourless to cloudy
We breath it out; it makes drinks fizzy; it dissolves in water producing a weak acid; it is associated with “global warming”
Carbon monoxide CO
No test
Poisonous gas, does not dissolve

24. Learning outcomes Success criteria
Know characteristic properties of carbon dioxide and carbon monoxide.
You can describe the properties of carbon dioxide and carbon monoxide, including:
State at room temperature
Flammability
You can state why high concentrations of carbon monoxide are dangerous.
You can state the test for carbon dioxide gas, naming the chemical you would use and the result.

25. S2 Chemistry Materials from the Earth
Fossil Fuels
S2 Chemistry
Materials from the Earth

26. Learning outcomes Success criteria
Know what is meant by a fossil fuel.
You can name the three main fossil fuels.
Know how fossil fuels are formed.
You can describe the formation of coal, oil and natural gas.
Understand why fossil fuels are a finite resource.
You can state what is meant by a finite resource.
You can explain why fossil fuels are likely to run out.

27. Which of these are fossil fuels?

34. Which fuels are fossil fuels?
The three main fossil fuels are:
Coal
Crude Oil
Natural Gas

35. Coal Formation of Coal: dead remains of trees covered in layers of mud
high temperature and pressure
over millions of years

36. Crude Oil Formation of Crude Oil: dead remains of marine life
covered in layers of sand
high temperature and pressure
over millions of years

38. Natural Gas Formation of Natural Gas: formed at the same time as oil
layer trapped on top of oil

40. Find out…
When are each of the three fossil fuels predicted to run out?

41. Learning outcomes Success criteria
Know what is meant by a fossil fuel.
You can name the three main fossil fuels.
Know how fossil fuels are formed.
You can describe the formation of coal, oil and natural gas.
Understand why fossil fuels are a finite resource.
You can state what is meant by a finite resource.
You can explain why fossil fuels are likely to run out.