NATIONAL QUALIFICATIONS CURRICULUM SUPPORT
Chemistry
Unit 2: Everyday Chemistry
1. Metals
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Qualifications support programme for Chemistry.
© Learning and Teaching Scotland 2009
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UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
Contents
Student material
4
Summary notes
48
Revision exercises
53
Revision exercise answers
59
UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
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STUDENT MATERIAL
Student material
2.1.1
In the Earth’s crust
Metallic elements are in green on
this periodic table.
Uncombined metals
 Copper, gold and silver are found in the Earth’s crust.
 They are found as metals alone.
Copper
Gold
Silver
Most metals are found combined with other elements in compounds .
Compounds which give useful metals are called ores.
Iron ore from Atlantic City
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UNIT 2: EVERYDAY CHEMISTRY – METALS
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STUDENT MATERIAL
In pairs, look at the samples of ores on display.
Find out which elements are in each ore.
Complete
Common name of ore
Chemical name
Symbols for elements
present
UNIT 2: EVERYDAY CHEMISTRY – METALS
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STUDENT MATERIAL
2.1.2
Obtaining metals
Heating with carbon
Extraction
 Metals we need for everyday things are made from their ores.
 Heating ores with carbon can extract metals.
The metal oxide is heated with carbon – oxygen combines with carbon
to make carbon dioxide.
Your teacher will show you how to make a metal from its ore by
heating with carbon.
Write a word equation for the reaction.
________ +________  ________ + ________
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UNIT 2: EVERYDAY CHEMISTRY – METALS
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STUDENT MATERIAL
2.1.3
The blast furnace
 Iron is one of the most important metals.
 It is needed to make steel.
 It is extracted from its ore in a blast furnace.
Label the parts of the diagram shown by the dotted line.
Use resources to find out about
the blast furnace.
UNIT 2: EVERYDAY CHEMISTRY – METALS
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STUDENT MATERIAL
Find out
(a)
What is loaded in at the top?
_________________________________________________
(b)
What is produced at the bottom?
_________________________________________________
(c)
Why is it called a blast furnace?
_________________________________________________
_________________________________________________
(d)
Complete the word equations for the reactions taking place at A, B
and C.
A.
_________________________________________________
B.
_________________________________________________
C.
_________________________________________________
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UNIT 2: EVERYDAY CHEMISTRY – METALS
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STUDENT MATERIAL
2.1.4
Obtaining metals
Using electricity
Many metals are taken from the ores by breaking
the compound with electricity.
Experiment: Breaking up compounds using electricity
Set up the circuit as shown.
Find out what is formed at the negative
electrode.
Notes
What kind of energy is used to break up the compound?
__________________________________________________________
What is formed at the negative electrode?
__________________________________________________________
How do you know this?
__________________________________________________________
UNIT 2: EVERYDAY CHEMISTRY – METALS
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STUDENT MATERIAL
Use resources to find out
how aluminium is
extracted from its ores
What I found out...
1.
______________________________________________
______________________________________________
2.
______________________________________________
______________________________________________
3.
______________________________________________
______________________________________________
4.
______________________________________________
______________________________________________
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UNIT 2: EVERYDAY CHEMISTRY – METALS
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STUDENT MATERIAL
Complete the sentences using the wordbank and resources.
 Bauxite is the ore from which most __________ is made.
 Chemicals made from ______ are used in the papermaking,
petroleum, and ________ industries.
 A white mineral salt called _____, used in drugs and in cosmetics
and dyes, also comes from the _____.
 Aluminium is made from aluminium ______, also called alumina.
 Aluminium oxide and other aluminium compounds occur in most
_________, rocks, and ______.
 _________ can be made cheaply only from bauxite.
aluminium
alum
minerals
bauxite
ore
soil
textile
oxide
aluminium
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STUDENT MATERIAL
2.1.5
Properties of metals
density
Properties
thermal
conductivity
malleability
electrical
conductivity
strength
Metals are used for different things, making use of their different
properties.
Iron is strong
Copper is used in wiring
Aluminium has
low density
Watch the investigation your teacher will plan and carry out using
metals.
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STUDENT MATERIAL
2.1.6
Alloys
An alloy is a mixture of metals or a mixture of metals with non-metals.
Metals are alloyed to change their properties for specific uses.
brass
solder
‘stainless’
steel
Alloys have important uses.
Look at some resources e.g. Books and internet, and find out more
about alloys.
UNIT 2: EVERYDAY CHEMISTRY – METALS
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STUDENT MATERIAL
Why are metals alloyed?
__________________________________________________________
__________________________________________________________
Fill in the table
Uses for alloys
Brass
14
Solder
UNIT 2: EVERYDAY CHEMISTRY – METALS
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‘Stainless’ steel
STUDENT MATERIAL
2.1.7
Metals and oxygen in the air
Reactive metals – metals that react easily with other substances.
Unreactive metals – do not react easily with other substances.
Metal oxides – metals that combine with oxygen in the air.
Your teacher will show you how lithium, potassium and sodium are
stored.
Fill in
A reactive metal is _______________________________________
_______________________________________________________
_______________________________________________________
An unreactive metal is ____________________________________
_______________________________________________________
_______________________________________________________
Which three metals are stored under oil?
________________ + ________________ + ________________
Why are they kept in oil? __________________________________
_______________________________________________________
Are they reactive or unreactive? _____________________________
UNIT 2: EVERYDAY CHEMISTRY – METALS
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STUDENT MATERIAL
2.1.8
Heating metals with oxygen
Many metals only react with oxygen when heated.
Metal oxides are produced in the reactions of metals
with oxygen.
(a)
Fill in
Metal
When heated with oxygen
Magnesium
Burns with a bright white flame
Tin
Aluminium
Iron
Zinc
Copper
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UNIT 2: EVERYDAY CHEMISTRY – METALS
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STUDENT MATERIAL
(b)
Give four safety points.
Safety in the
experiment
goggles
(c)
heat-proof mat
hands
Place each metal in order of reactivity.
least reactive
tin
Bunsen flame
copper
most reactive
zinc
aluminium
magnesium
UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
iron
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STUDENT MATERIAL
The word equation for reactions of metals with oxygen is :
metal + oxygen  metal oxide
eg magnesium + oxygen  magnesium oxide
(d)
Write the word equation for the reaction of
 zinc with oxygen.
_________+___________  ______________
 copper with oxygen
_________+___________  ______________
 iron with oxygen
_________+___________  ______________
 tin with oxygen
_________+___________  ______________
 aluminium with oxygen
_________+___________  ______________
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UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
STUDENT MATERIAL
2.1.9
Metals with water (i)
lithium
have to be protected
from the atmosphere
potassium
sodium
kept covered in oil or they
would be dangerous
Your teacher will show you the reaction of lithium, potassium and
sodium with water.
UNIT 2: EVERYDAY CHEMISTRY – METALS
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STUDENT MATERIAL
You will test the reaction of calcium and iron with water.
Results
Metal
Reaction with water
Lithium
Potassium
Sodium
Calcium
Iron
(b)
Put the metals in order of increasing reactivity.
least reactive
sodium
20
potassium
most reactive
calcium
UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
iron
lithium
STUDENT MATERIAL
2.1.10
Testing for hydrogen
The gas given off when a metal reacts with water could be hydrogen or
oxygen.
oxygen relights a glowing splint
Carry out this experiment to find a test for hydrogen:
Notes
(a)
Complete the table.
What happens when a glowing splint is put into test-tubes with
Gas
Burning splint
Nitrogen
Oxygen
Hydrogen
Carbon dioxide
(b)
What is the test for hydrogen?
______________________________________________________
UNIT 2: EVERYDAY CHEMISTRY – METALS
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STUDENT MATERIAL
2.1.11
Metals with water (ii)
A metal which reacts with water forms the metal
hydroxide and a gas is given off.
The rate of reaction of calcium with water enables the gas to be
collected and identified.
Your teacher will show you how to identify the gas produced when a
metal reacts with water.
Fill in
(a)
What happens when calcium is placed in cold wat er?
______________________________________________________
(b)
Which gas is produced when calcium reacts with water?
______________________________________________________
(c)
How do you know the gas is present?
______________________________________________________
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UNIT 2: EVERYDAY CHEMISTRY – METALS
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STUDENT MATERIAL
(d)
Write the word equation for the reaction of calcium with water.
_________ + _________  _________ + _________
Do the same experiment with magnesium and water.
(e)
What happens when magnesium is placed in cold water?
______________________________________________________
(f)
Put in order of how these react with water:
least reactive
calcium
magnesium
most reactive
lithium
potassium
sodium
UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
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STUDENT MATERIAL
2.1.12
Metals with dilute acid
Reactions of metals with an acid make hydrogen gas and a sal t.
Some metals react very well with dilute hydrochloric acid.
Copper
Gold
Silver
DO NOT REACT
Your teacher will show you how to find the gas produced when a
metal reacts with:
 dilute hydrochloric acid
 dilute sulphuric acid.
Method
1.
Half fill a test-tube with hydrochloric acid.
2.
Add 1 spatulaful of metal.
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UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
STUDENT MATERIAL
3.
Look and see how well it fizzes.
4.
Test the gas given off with a lighted taper – Does it burn with a
pop?
5.
Do the same for all the metals.
6.
Do the same experiment again with sulphuric acid.
Fill in your results
Reaction with
Metal
Hydrochloric acid
Sulphuric acid
Magnesium
Iron
Zinc
Fizzes vigorously
Burns with a pop
Fizzes fast
Taper goes out
Fizzes slow
Taper relights
UNIT 2: EVERYDAY CHEMISTRY – METALS
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STUDENT MATERIAL
Fill in
(a)
Which gas is produced when a metal reacts with dilute acid?




(b)
helium
oxygen
hydrogen
nitrogen.
The gas can be identified because it:
 relights a glowing splint
 burns with a pop
 turns limewater milky.
(c)
Which three metals do not react with dilute acid?
___________
(d)
___________
__________
Complete the word equation for the reaction of magnesium with
dilute sulphuric acid.
magnesium + ____________  _________ + __________
(e)
Complete the word equation for the reaction of zinc with dilute
hydrochloric acid.
zinc+ ____________  _________ + __________
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UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
STUDENT MATERIAL
Metal
Reactivity
Potassium
Most
reactive
Reaction with
Oxygen
Lithium
Metals
which
react
with
dilute
acid
Metals
which
react with
oxygen
Magnesium
Dilute acid
Metals
which
react with
water
Sodium
Calcium
Water
Aluminium
Zinc
Iron
Tin
Lead
No reaction
Copper
Mercury
Silver
No reaction
No reaction
Gold
Least
reactive
UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
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STUDENT MATERIAL
Use the table to complete the sentences.
(a)
The most reactive metal is ________________.
(b)
The least reactive metal is ________________.
(c)
A metal which does not react with oxygen is _____________.
(d)
The five metals which react with water are _____________
_____________
_____________
_____________
_____________
(e)
___________ would not react with hydrochloric acid.
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UNIT 2: EVERYDAY CHEMISTRY – METALS
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STUDENT MATERIAL
Word equations for reactions of metals
THINK!
A
Metal + oxygen  metal oxide
eg
magnesium + oxygen  magnesium oxide
B
Metal + water  metal hydroxide + hydrogen
eg
sodium + water  sodium hydroxide + hydrogen
C
Metal + acid  salt + hydrogen
What is a salt?
This depends on the acid used
Acid
Salt
hydrochloric acid
metal chloride
sulphuric acid
metal sulphate
eg
calcium + hydrochloric acid  calcium chloride + hydrogen
iron + sulphuric acid  iron sulphate + hydrogen
UNIT 2: EVERYDAY CHEMISTRY – METALS
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STUDENT MATERIAL
Now complete the word equations below.
(a)
Zinc + oxygen  ______________________
(b)
Lead + oxygen  ______________________
(c)
Calcium + water  ______________________
(d)
Potassium + water  ______________________
(e)
Magnesium + hydrochloric acid  ______________________
(f)
Tin + sulphuric acid  ______________________
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UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
STUDENT MATERIAL
2.1.13
A problem with metals
Corrosion
 When some metals are left in the open air, they tend to break up at
the surface.
 The metal object gradually disappears as the surface flakes off.
 The surface changes from an element to a compound.
Rusting
 The corrosion of iron.
 Iron breaks up and flakes.
 Iron loses its strength.
UNIT 2: EVERYDAY CHEMISTRY – METALS
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STUDENT MATERIAL
Experiment: What causes rusting?
Method
1.
2.
3.
Set up three test-tubes as shown above.
Leave for three days.
Look and see what the metal looks like.
Note
Note
 The solubility of air in
water decreases the
warmer the water gets.
 Calcium chloride is a drying
agent and removes moisture
from the air.
 Boiling water has little
dissolved air.
Look at the nails and fill in the
answers below.
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UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
STUDENT MATERIAL
Answers
(a)
In which test-tube does the nail rust? _____
(b)
Fill in the words.
The ____ in test-tube _ does not rust because the ___ cannot reach
the nail.
The ____ in test-tube _ does not ____ because the ________ has
been removed.
nail
(c)
moisture
A
rust
B
air
nail
Give two things needed for rusting.
_____________
_______________
Now check your answers with the
person beside you. Can you add
anything else?
UNIT 2: EVERYDAY CHEMISTRY – METALS
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STUDENT MATERIAL
2.1.14
A rust indicator
 Rust is not an element.
 When iron rusts the iron atoms become iron ions.
 A rust indicator is a compound that detects iron ions.
Experiment: Finding an indicator for rusting
Method
1.
Fill a third of each test-tube with iron sulphate.
2.
Test-tube 1: add few drops of indicator A.
3.
Test-tube 2: add few drops of indicator B.
4.
Test-tube 3: add few drops of indicator C.
5.
Test-tube 4: add few drops of indicator D.
6.
Watch what happens in each test-tube.
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UNIT 2: EVERYDAY CHEMISTRY – METALS
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STUDENT MATERIAL
Fill in your results
Indicator
Effect on iron sulphate
A
B
C
D
Notes
(a)
Which indicator can be used as a rust indicator?
A
(b)
B
C
D
What was the colour change?
______________________________________________________
Now check your answers with the
person beside you. Can you add
anything else?
UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
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STUDENT MATERIAL
2.1.15
Speeding up rusting
Rust indicator can be used to measure the amount of rusting.
The deeper the blue colour, the greater the rusting
Notes
(a)
Use a blue colour to show the
amount of rusting in each test-tube.
(b)
Why do you have the test-tube of pure water?
______________________________________________________
(c)
What does acid rain do to the speed of rusting?
______________________________________________________
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© Learning and Teaching Scotland 2009
STUDENT MATERIAL
(d)
What does salt do to the speed of rusting?
______________________________________________________
(e)
How does putting salt on the roads in winter affect the speed of
rusting of a car?
______________________________________________________
(f)
Why should you wash your car more often if you live near the
sea?
______________________________________________________
(g)
Why do cars in the city rust faster than cars in the country?
______________________________________________________
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STUDENT MATERIAL
2.1.16
Stopping corrosion (i)
In the UK millions of pounds are spent fighting corrosion , eg people
will buy a new car because their old one is rusted.
 Oxygen and water must be present for iron to form rust.
 Iron can be protected from rusting by stopping air and water coming
into contact with the iron.
 Painting, greasing, tin-plating and coating with plastic form a surface
barrier against air and water, providing protection against corrosion.
Ways of making a surface barrier to air and water
Fill in
Ways to protect iron from rusting
1.
2.
3.
4.
Which metal is used to galvanise iron? Circle one.
lead
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copper
UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
zinc
STUDENT MATERIAL
Electroplating
 Another surface barrier to air and water.
 Electricity is used to make a thin layer of a new metal, which is less
likely to corrode.
 Covers the metal to be protected.
Your teacher will show you how to electroplate a metal .
Notes
(a)
What is meant by electroplating?
______________________________________________________
______________________________________________________
(b)
Why does this protect a metal from corrosion?
______________________________________________________
______________________________________________________
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STUDENT MATERIAL
2.1.17
Stopping corrosion (ii)
Iron can also be attached to certain other metals to protect them . This is
a very different method to using a surface barrier.
Notes
(a)
Colour the dishes to show the amounts of rusting in each.
(b)
Look at page 6 in the data booklet.
What happens to the speed of rusting when iron is connected to a
metal that is more reactive than the iron itself?
______________________________________________________
______________________________________________________
(c)
Why do you think bags of scrap magnesium are attached to
underground iron and steel pipes?
______________________________________________________
______________________________________________________
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UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
STUDENT MATERIAL
2.1.18
Protecting aluminium from corrosion
 Aluminium is the second most important
metal used today.
 Aluminium is a fairly reactive metal.
 It needs to be protected.
Experiment: Finding out more about
aluminium
Method
1.
Half fill two test-tubes with hydrochloric acid.
2.
Put a piece of clean aluminium in one.
3.
Put a piece of oxidised aluminium in the other.
4.
Add a few drops of detergent to speed up the reaction.
5.
Watch what happens.
UNIT 2: EVERYDAY CHEMISTRY – METALS
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STUDENT MATERIAL
Fill in
(a)
Label the diagram to show the results of the experiment .
Aluminium is slow to react since it is usually covered by a thin layer
of aluminium oxide.
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STUDENT MATERIAL
2.1.19
Batteries
 Batteries come in all shapes and
sizes for different uses.
 When in use the chemicals in the
battery react to make electricity.
 Chemical energy is changed to
electrical energy.
 When all the chemicals have
been used up, the battery can no
longer make electricity – the
battery is ‘dead’.
 Some batteries can be recharged, eg the
lead–acid battery in a car and nickel–
cadmium batteries. These batteries can be
used over and over again.
Look at the display of batteries.
Complete the table.
Describe battery
What is it used for?
UNIT 2: EVERYDAY CHEMISTRY – METALS
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STUDENT MATERIAL
Fill in
(a)
Where does the electricity come from in a battery?
______________________________________________________
(b)
What energy change takes place?
______________________________________________________
(c)
Why do batteries become ‘dead’ after being used for a long time?
______________________________________________________
(d)
What is a rechargeable battery?
______________________________________________________
(e)
Give two examples of rechargeable batteries.
______________________________________________________
______________________________________________________
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UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
STUDENT MATERIAL
2.1.20
Making electricity
 Electricity can be made by connecting
different metals to make a cell.
 A solution with ions is needed to
complete the circuit between the metals.
Experiment
The voltage between different pairs of metals varies.
Fill in your results
Metal 2
Voltage in volts
Magnesium
Magnesium
Magnesium
Magnesium
UNIT 2: EVERYDAY CHEMISTRY – METALS
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STUDENT MATERIAL
Circle the correct answer
(a)
Magnesium joined to copper/zinc gives the highest voltage.
Now look at the reactivity series on page 6 of the data booklet.
(b)
Metals that are far apart in the reactivity series make a high/low
voltage.
(c)
Magnesium joined to silver will produce a higher/lower voltage
than magnesium joined to copper.
(d)
When zinc is attached to iron, the voltage will be higher/lower
than zinc attached to tin.
(e)
When iron is attached to copper, the voltage will be higher/lower
than iron attached to magnesium.
Now check your answers with the
person beside you. Can you add
anything else?
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© Learning and Teaching Scotland 2009
SUMMARY NOTES
Summary notes
You must know the following to help you in the end of unit
assessment.
1.
Uses
Some metals, including gold, silver and copper, are found unc ombined
in the Earth’s crust.
Most metals are found combined with other elements.
Metal elements and carbon (graphite) are conductors of electricity.
Most non-metal elements are non-conductors of electricity.
The specific properties of metals are as follows:
Properties
strength
thermal
conductivity
malleability
electrical
conductivity
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UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
density
SUMMARY NOTES
Metals are used for different things, making use of their different
properties.
An alloy is a mixture of metals, or of metals with non -metals.
Alloys, including brass, solder and
‘stainless’ steel, have important
uses.
48
UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
SUMMARY NOTES
2.
Reactions
Reactive metals – metals that react very easily with other substances.
Unreactive metals – metals that do not react easily with other
substances.
Metal oxides – these are formed by metals which combine with the
oxygen in the air.
Metal
What is formed when heated
with oxygen
Magnesium
Magnesium oxide
Zinc
Zinc oxide
Copper
Copper oxide
Lead
Lead oxide
Tin
Tin oxide
Lithium
Lithium oxide
The reaction of metals with acid often produces hydrogen:
 Some metals react very well with dilute hydrochloric acid.
 Copper, silver and gold do not react.
 Hydrogen is produced when a metal reacts with dilute acid.
The test for hydrogen is that it burns with a ‘pop’.
UNIT 2: EVERYDAY CHEMISTRY – METALS
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SUMMARY NOTES
3.
Corrosion
When some metals are left in the open air, they tend to break up at the
surface.
The metal object disappears as the surface flakes off.
The surface changes from an element to a compound.
 Corrosion is a chemical reaction that involves the surface of a metal
changing from an element to a compound.
 Acid rain increases the rate of corrosion.
 Salt spread on roads increases the rate of corrosion on car bodywork.
 Painting, greasing, tin-plating and coating with plastic give a surface
barrier to air and water that can provide protection against corrosion.
Rusting
When iron rusts it breaks up and flakes.
Iron loses its strength when it rusts.




Rusting is the corrosion of iron.
Rusting results in a loss of structural strength.
Both oxygen (from the air) and water are required for rusting.
Rust indicator can be used to show the extent of the rusting process.
Rust indicator can be used to measure the amount of rusting.
The more blue colour the more rusting.
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UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
SUMMARY NOTES
4.
Batteries
 In a battery, electricity comes from a chemical reaction.
 Batteries require to be replaced due to the chemicals being used up in
the reaction.
When all the chemicals have been used up, the battery can no longer
make electricity – the battery is ‘dead’.
Examples of rechargeable batteries include:
 the lead–acid battery in a car
 the nickel–cadmium battery in portable radios and personal stereos.
These batteries can be used over and over again.
UNIT 2: EVERYDAY CHEMISTRY – METALS
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REVISION EXERCISES
Revision exercises
1.
Uses
1.
Fill in the missing words. Use the wordbank at the bottom of the
page.
(a)
Some metals, including gold, silver and copper, are found
__________ in the Earth’s crust.
(b)
Most metals are found ________ with other elements.
(c)
Metal elements and carbon (graphite) are __________ of
electricity.
(d)
Most non-metal ________ are non-conductors of electricity.
(e)
The use we make of a metal depends on its specific
__________.
elements
properties
uncombined
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UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
combined
conductors
REVISION EXERCISES
2.
Complete the following sentences by selecting the correct word
from the wordbank below.
(a)
An _____ is a mixture of metals.
(b)
An alloy can also be a _______ of metals with non-metals.
(c)
_____ is an alloy.
(d)
Alloys have important ____.
(e)
_________ _____ is an alloy.
brass
alloy
mixture
2.
Reactions
1.
Use arrows to match up the boxes.
uses
stainless steel
reactive
Does not react easily
with other substances
unreactive
A few metals which
combine with the oxygen
in the air
metal oxides
Metals which react very
easily with other
substances
UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
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REVISION EXERCISES
2.
Complete the following word equations.
tin + oxygen  ___ oxide
copper + ______  copper oxide
____ + oxygen  lead oxide
magnesium + oxygen  magnesium _____
3.
Answer true (T) or false (F).
Copper, silver and gold do not react with acid.
Oxygen is produced when metal reacts with dilute acid.
All metals react well with dilute hydrochloric acid.
The test for hydrogen is that it burns with a pop.
Reactions of metals with acid produce hydrogen.
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UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
REVISION EXERCISES
3.
Corrosion
1.
Corrosion is a ________ reaction that
involves the _______ of a metal
changing from an _______ to a
________.
Acid ____ increases the rate of
_________.
Salt spread on roads increases
the rate of _________ on a car’s
__________
Painting, ________, tin-plating
and coating with plastic give a
surface barrier to ___ and _____
which can protect against
_________.
UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
55
REVISION EXERCISES
Rusting
2.
 _______ is the corrosion of iron.
 Rusting results in the loss of structural ________.
 Oxygen and _____ are needed for rusting.
 Rust ________ is used to show the extent of rusting.
 When ____ rusts it breaks and flakes.
 Iron loses its ________ when it rusts.
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UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
REVISION EXERCISES
4.
Batteries
1.
Chemicals are used
up in _________.
In a battery,
electricity comes
from a
________reaction.
2. Two types of rechargeable batteries are:
1.
2.
Now look over the summary sheets and study for the assessment.
UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
57
REVISION EXERCISE ANSWERS
Revision exercise answers
1.
Uses
1.
Fill in the missing words. Use the wordbank at the bottom of the
page.
(a)
Some metals, including gold silver and copper, are found
uncombined in the Earth’s crust.
(b)
Most metals are found combined with other elements.
(c)
Metal elements and carbon (graphite) are
conductors of electricity.
(d)
Most non-metal elements are non-conductors of electricity.
(e)
The use we make of a metal depends on its specific
properties.
2.
Complete the following sentences.
Select the correct words from the wordbank below.
58
(a)
An alloy is a mixture of metals.
(b)
An alloy can also be a mixture of metals with non-metals.
(c)
Brass is an alloy.
(d)
Alloys have important uses.
(e)
Stainless steel is an alloy.
UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
REVISION EXERCISE ANSWERS
2.
Reactions
1.
Use arrows to match the boxes.
reactive
 Does not react easily
with other substances
unreactive
 A few metals which
combine with the
oxygen in the air
metal oxides
 Metals which react
very easily with other
substances
2.
Complete the following word equations.
tin + oxygen  tin oxide
copper + oxygen  copper oxide
lead + oxygen  lead oxide
magnesium + oxygen  magnesium oxide
UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
59
REVISION EXERCISE ANSWERS
3.
Answer true (T) or false (F).
Copper, silver and gold do not react with acid.
T
Oxygen is produced when metal reacts with dilute acid.
F
All metals react well with dilute hydrochloric acid.
F
The test for hydrogen is that it burns with a pop.
T
Reactions of metals with acid produce hydrogen.
T
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UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
REVISION EXERCISE ANSWERS
3.
Corrosion
1.
Corrosion is a chemical reaction which
involves the surface of a metal changing
from an element to a compound.
Acid rain increases the rate of
corrosion.
Salt spread on roads increases
the rate of corrosion on a car’s
bodywork.
Painting, greasing, tin-plating
and coating with plastic give a
surface barrier to air and water
that can protect against
corrosion.
UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
61
REVISION EXERCISE ANSWERS
Rusting
2.
 Rusting is the corrosion of iron.
 Rusting results in the loss of structural strength.
 Oxygen and water are needed for rusting.
 Rust indicator is used to show the extent of rusting.
 When iron rusts it breaks and flakes.
 Iron loses its strength when it rusts.
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UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
REVISION EXERCISE ANSWERS
4.
Batteries
1.
In a battery,
electricity comes
from a chemical
reaction.
Chemicals are used
up in reactions.
2. Two types of rechargeable batteries are:
1. Lead–acid
2. Nickel–
cadmium
Now look over the summary sheets and study for the assessment.
UNIT 2: EVERYDAY CHEMISTRY – METALS
© Learning and Teaching Scotland 2009
63