West Lothian Council
Lorna C. Webster
1
Making acid gases
Read
We can make acid gases by reacting non-metal elements like
carbon, sulphur and nitrogen with oxygen. This joins the
elements together to make
 Carbon dioxide
 Sulphur dioxide
 Nitrogen dioxide
All of these compounds are acid gases because when they
dissolve in water they turn it into acid.
Your teacher may show you how to make these three acid gases.
Write a heading and try the work below.
1. List the names of the three non-metal elements that can be
used to make acid gases.
2. What element do these join with to make the acid gases?
3. List the names of the three acid gases.
4. Why are these gases called acid gases?
5. Collect the making carbon dioxide sheet.
a) fill the sheet in with what you saw in the demonstration.
b) colour the pH indicator in with the correct colour.
c) stick the sheet into your jotter
d) then underneath it write a word equation for the
reaction (ask for help if you cannot remember how to do
this).
6. Collect the making sulphur dioxide sheet.
a) fill the sheet in with what you saw in the demonstration.
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b)
c)
d)
colour the pH indicator in with the correct colour.
stick the sheet into your jotter
then underneath it write a word equation for the
reaction (ask for help if you cannot remember how to do
this).
7. Collect the making nitrogen dioxide sheet.
a) fill the sheet in with what you saw in the demonstration.
b) colour the pH indicator in with the correct colour.
c) stick the sheet into your jotter
d) then underneath it write a word equation for the
reaction (ask for help if you cannot remember how to do
this).
8. Write down the formula for
a) carbon dioxide
b) sulphur dioxide
c) nitrogen dioxide
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Where do acid gases come from?
Read
Carbon dioxide
Carbon dioxide is made when fossil fuels like coal or oil or gas
or petrol are burned in air. When the fuels burn, the carbon in
the fuels joins with oxygen to make carbon dioxide gas. A lot
of carbon dioxide gas is made on earth since we burn a lot of
fossil fuels for energy in power stations and there are millions
of cars on the roads that produce carbon dioxide when the
petrol is burned in the engine.
Sulphur dioxide
Sulphur dioxide also comes from burning fossil fuels. This
happens because fossil fuels have small amounts of sulphur in
them. When the fuels burn the sulphur in the fuel joins with
oxygen to make sulphur dioxide gas.
Nitrogen dioxide
Nitrogen dioxide comes from car
exhausts but it is not because of
the petrol that is burned. Cars
need air to make them work. The
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main gases in air are nitrogen and oxygen. In the engine there
are parts called spark plugs. These spark plugs make an
electrical spark and this makes the nitrogen and oxygen join
together to make nitrogen dioxide gas.
Nitrogen dioxide is also made naturally when a
lightning storm happens because the lightning
makes the nitrogen and oxygen in the air join
together.
Write a heading and try the work below.
1. Describe how carbon dioxide is made?
2. Why is the amount of carbon dioxide in earth’s air
increasing?
3. Describe how sulphur dioxide is made.
4. Where does nitrogen dioxide come from?
5. What percentage of the air is
a) nitrogen
b) oxygen
6. Explain what happens in a car engine to make nitrogen
dioxide.
7. Explain why nitrogen dioxide can also be made naturally.
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What does acid rain do?
Read
When acid rain falls it can cause damage to many things.
When acid rain falls onto soil it can
turn the soil too acidic and this can
cause plants to die. Farmers often
add lime to their fields to
neutralise the acid in the soil. The
acid rain can also burn the leaves
of the plants and often the plant
will die because it needs its leaves
to make food.
Rivers and lakes in areas where acid rain falls can gradually turn
more acidic. The fish and plant life in these rivers, stream and
lakes are often unable to survive in the
acid water. Many lakes in Sweden are
turning acid because of acid rain and the
government are buying tonnes of lime to
put in the lakes to neutralise the acid
and try to save the fish and plants.
You have already learned that some metals will react with acid.
Iron and steel are metals that will react with acid so when acid
rain falls onto building and structures
made of these metals the metals will
react and become damaged and
weakened. This is happening to the
Forth Rail bridge. The acid rain is
making it rust faster.
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You also already know that chemicals called carbonates will
react with acid to make carbon
dioxide gas. Many buildings are
made from stone that contains
these carbonates so when acid
rain falls, the stones react and
become damaged and weakened.
Some very old monuments like the
Taj Mahal, the Sphinx and
Cleopatra’s needle are beginning to
be eaten away by acid rain and
scientists are trying to find ways to
protect them.
Write a heading and try the work below.
1. What happens to soil when acid rain falls?
2. What affect does this have on plant growth?
3. Why do farmers often add lime to their fields?
4. What happens to animal and plant life in rivers where there is
a lot of acid rain?
5. Why does lime help stop this?
6. Sweden is a country that does not make much acid rain. Can
you suggest why they have such a problem with it? (clue:
think of cloud and the weather)
7. Name two metals that react with acid.
8. What happens to structures that are made of iron or steel
when acid rain falls on them?
9. What is the name of the gas that is made when acid reacts
with carbonates?
10. Why can some stone buildings be damaged and weakened by
acid rain?
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Your teacher may ask you to
 Do a poster of how acid rain is made or the damage it can do.
 Do an experiment (1.53.1) about lime and neutralising acids.
 Do an experiment (1.53.2) about acid in the water from
different places.
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