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1
Chemistry– Metals + acids Name …………………………………………………………………….
Part I was present
for this lesson
(tick)
Red, amber or
Green?
R A G
1 3.1 Acids and metals
2 3.2 Metals and oxygen
3 3.3 Metals and water
4 3.4 Metals displacement
5 3.5 Extracting metals
6 3.6 Ceramics
7 3.7 Polymers
8 3.8 Composites
9 3.9 Chapter summary
Mini test 1 Mark: Grade:
Successes in this topic:
Developments:
A community of VALUED individuals
Versatile Aspirational Learning Understanding Engaged – Determined
2
Learning homework for this topic: This will be on Show My Homework. Please ask you parents to sign that you have been learning it. A good way would be to make a poster.
Probably done in yr. 10 for most groups.
3
Key word Definition
carbon fibre A material made of thin tubes of carbon.
ceramic A compound such as a metal silicate or oxide that is hard,
strong, and has a high melting point.
composite A mixture of materials with properties that are a combination
of those of the materials in it.
displace A more reactive metal displaces – or pushes out – a less
reactive metal from its compound.
displacement reaction In a displacement reaction, a more reactive metal displaces
– or pushes out – a less reactive metal from its compound.
metal
Elements on the left of the stepped line of the Periodic Table.
Most elements are metals. They are good conductors of
energy and electricity.
natural polymer Polymers made by plants and animals, including wool,
cotton, and rubber.
ore A rock that you can extract a metal from.
polymer A substance made up of very long molecules.
reactive A substance is reactive if it reacts vigorously with substances
such as dilute acids and water.
reactivity series A list of metals in order of how vigorously they react.
state symbol
A state symbol gives the state of a substance in a chemical
equation. (s) means solid, (l) means liquid, (g) means gas,
and (aq) means dissolved in water.
synthetic polymer A substance made up of very long molecules that does not
occur naturally.
thermite reaction Reaction of aluminium with iron oxide to make aluminium
oxide and iron.
4
CWK How do metals react with acid? ………/……./………..
Lesson Developing Secure Extending
C2 3.1
Acids and metals
I can describe what
happens when metals
react with acids.
I can compare the
reactions of different
metals with dilute acids.
I can use formula
equations to show what
happens when metals
react in different acids.
I can state that hydrogen
gas makes a squeaky pop
when lit.
I can explain the test
for hydrogen gas.
I can use word and
formula equations to
explain the test for
hydrogen gas.
A. The products in the reaction
between a metal and an acid are a
salt and ………………………………… gas.
B. The test for hydrogen gas is
…………………………………………………………….
…………………………………………………………….
…………………………………………………………….
…………………………………………………………….
…………………………………………………………….
Key words
hydrogen lit splint squeaky pop test tube acid salt
5
Reacting metals with acid
Setting the scene
When metals react with acids they form a salt and hydrogen. But not all metals react
readily with acid. You will use the signs of a reaction to identify which metals react
more readily, and which react least readily.
Aims
In this practical you will:
react four different metals with an acid to decide which react most vigorously
make observations of the reactions to decide how vigorously the reactions are
occurring. You will be working scientifically to:
interpret your observations to decide which metal reacts most vigorously with acid
make and record observations
present observations using tables
use appropriate methods, paying attention to associated risks.
Safety
Wear eye protection throughout the practical and wash spills off skin immediately.
Magnesium is flammable. Keep away from naked flames.
Iron filings can be irritating to eyes. Do not rub your eyes. Clear up unused iron
immediately.
Lead is toxic. Wash your hands after handling.
Take care when handling test tubes as they can become hot and bubble during the
experiment.
Equipment and materials
eye protection, 0.5M hydrochloric acid, test tubes, zinc, lead, iron, magnesium ribbon,
test-tube rack, copper sulphate solution
Method
1 Put 2cm of acid into a test tube.
2 Place a small piece of magnesium ribbon into the acid.
4 Wait for a few minutes and draw what happens - draw how many bubbles you see.
5 Repeat the method using zinc, lead, and iron.
Results – draw what happens:
6
Metals Observations
Magnesium
Zinc
Iron
Lead
Questions
1 Tick the observations that suggested a reaction was occurring. Challenge
The acid fizzed and bubbles were given off.
The metal changed colour.
The same amount of acid was used for each experiment.
The temperature of the acid went up.
Mg Magnesium Zn Zinc Fe Iron Pb Lead
7
2 List the four metals in order of increasing reactivity with the acid. Put 1 for the most
reactive, 2 for the second most reactive and so on. Extra challenge.
Magnesium ………………….
Lead ………………….
Iron ………………….
Zinc ………………….
Explain how you decided the order they should be in.
E.g. I chose magnesium as …………………………………………… reactive because it gave the most
………………………………………. when added to acid.
3 How you can find out if you have produced hydrogen gas. Super challenge.
Use a glowing spill, if it is hydrogen it will relight
Use a lit spill, if it is hydrogen there will be a squeaky pop.
Use limewater, if it is hydrogen it will turn the limewater cloudy.
When an acid reacts with a metal a salt and water are formed.
Acid + metal salt + water
If the metal reacted with citric acid then a metal citrate was made. Super challenge +
The type of acid used decides which salt you get.
Hydrochloric acid makes a CHLORIDE
Sulphuric acid makes a SULPHATE
Nitric acid makes a NITRATE
4 Complete the following word equations for the reactions between the four metals
and hydrochloric acid:
magnesium + hydrochloric acid → ……………………………….. + …………………………………
zinc + hydrochloric acid → ………………………………… + ………………………………………….
lead + hydrochloric acid → ……………………………….. + …………………………………………..
iron + hydrochloric acid → ……………………………….. + …………………………………………...
8
What have you learned this lesson?
This lesson I learned about:
………………………………………………………………………………………………………………………………………………
……………………………………………………………………………………………………………………………………………… Prove it tasks for 3.1
Choose your question
Summary questions
Extra challenge Super challenge
9
B) The label on a bottle of kitchen cleaner says:
It leaves kitchen and bathroom surfaces bright and shiny.
Another part of the label says:
Contains sulphamic acid
Irritating to eyes and skin
Keep out of reach of children
(i) The chart shows the colour of universal indicator in different solutions.
type of solution strongly acidic
weakly acidic
neutral weakly alkaline
strongly alkaline
colour of universal indicator
red orange green blue purple
What colour will the kitchen cleaner turn universal indicator?
..................................................................………. 1 mark
(ii) Which hazard label do you expect to see on the bottle? Write the correct letter from the list above.
............................................…
1 mark
Maximum 4 marks
CWK How do metals with oxygen? …………/………/…………………..
10
Lesson Developing Secure Extending
C2 3.2 Metals and oxygen
I can state the product of
the reaction between
metals and oxygen.
I can compare the
reactions of different
metals with oxygen.
I can explain the
reactivity of metals
according to how they
react with oxygen.
I can identify state
symbols from an equation.
I can use state symbols
in balanced formula
equations.
I can construct balanced
equations that include
state symbols.
A. i) The state symbol for a
substance in the gas state is
…………………………
(s) means ……………………………
ii) Predict the symbol for a
substance in the liquid state
…………………………………………………..
B.
Meta l i) …………………………………………………
Metal ii) ………………………………………………..
iii) Give the word equation for calcium
reacting with oxygen: ……………………. + oxygen ………………………………………
How do metals react with oxygen? demonstration
Key words
gas solid liquid magnesium zinc calcium calcium oxide magnesium oxide
11
Setting the scene
Some metals react more easily with oxygen than others. You can usually tell which
metals react more easily by watching them burn.
Aims
In this practical you will:
Watch your teacher react metals with oxygen by burning them in air
record your observations to decide which metal reacts most easily with oxygen.
make and record experimental observations
interpret your observations to decide which metal reacts most vigorously
present explanations of your conclusions.
Safety - Wear eye protection throughout the practical demonstration
Magnesium is highly flammable. Do not look directly at burning magnesium.
Iron filings can be irritating to eyes.
Calcium is highly flammable. Do not look directly at burning calcium.
Your teacher may ask you to sit behind a safety screen for parts of the
demonstration.
Equipment and materials
eye protection, magnesium ribbon, iron wool, copper strips, aluminium strip/foil,
black tongs, test tubes, heatproof mat, safety screen
spirit (methanol or ethanol) burner
Use this table to record your observations.
Metal
reacting Observations Equation to represent the reaction
iron
Iron + oxygen iron oxide
……. + ………. …………………..
aluminium
Aluminium + oxygen …………….. oxide
……… + ………. …………………..
copper
Copper + ……………… copper oxide
…… + ………. …………………..
magnesium
magnesium+ …………….. ……………..oxide
………. + ………. ……………………..
Prove it task 2
12
Choose from the following list of chemical formulae to help you complete the word
equations [super challenge] and symbol equations [Super challenge +] :
Oxygen copper oxide magnesium oxide aluminium oxide
Mg Cu Al Fe O2 FeO Al2O3 CuO MgO
Extension. You may include state symbols in your equations.
State symbol Meaning Example
(s) solid copper strips
(l) liquid water
(g) gas oxygen
(aq) aqueous solution salty water
……………………. + ………………………. …………………………………
……………………. + ………………………. …………………………………
……………………. + ………………………. …………………………………
……………………. + ………………………. …………………………………
Method for teacher demo.
1 Collect one sample of each metal and a pair of tongs.
2 Holding each sample using the pair of tongs, heat in a blue flame for 30 seconds
to a minute.
3 Record your observations about each reaction in an appropriate results table.
4 Write an equation to represent the reactions you have seen. Include state symbols.
Questions
1 List the metals in order of how well they reacted with oxygen. Start with the most reactive
metal.
Most reactive ………………………………………
……………………………………..
……………………………………..
Least reactive ……………………………………..
13
2 Explain how your observations helped you to put the metals into the order in
Question 1.
Extension
1 Explain what reactive means.
2 Using your observations, complete the following sentences:
is more reactive than but less
reactive than .
I know this because
3 Lithium reacts explosively with oxygen in a Bunsen burner flame. Use this
information and your observations above to predict the reactivity of lithium
compared to the metals you have observed in this practical. Explain your answer.
14
Summary /Prove it Tasks
1. Complete the sentences.
Some metals burn vigorously in air, for example ……………………………. The products are
Metal ………………………………. Some metals form an oxide layer on their surface when heated,
for example …………………………………….. Some metals, for example ……………………………….. , do not
react with oxygen. (4 marks)
Extra Challenge
…………………………… + ………………………………….. ……………………………………………
Super Challenge
…………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………… ……………………………………………………………………………………………………………………
gold copper magnesium oxide
15
Creative Challenge
…………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………… ……………………………………………………………………………………………………………………
What have you learned this lesson?
………………………………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………………………………
16
CWK How do metals with water? …………/………/…………………..
Developing Secure Extending
C2 3.3 Metals and water
I can state the products
of the reaction between
metals and water.
I can compare the
reactions of metals with
water.
I can link a metal’s
reaction with its place in
the reactivity series.
I can state whether a
metal is more or less
reactive than another
metal.
I can use the reactivity
series to predict
reactions.
I can explain predictions
made about a metal’s
reactivity.
A. The products of the
reaction of calcium and
water are:
…………………………………….. and
…………………………………………….
B. What are the state
symbols for substances in
the following states:
Liquid
…………………………….
Dissolved in water
……………………………………….
Key words
water hydrogen calcium hydroxide solid liquid gas (s) (l) (g) (aq) steam
17
C Name two metals that react
with steam but not cold water:
……………………………………………………………
...Na + .…H2O .…H2 +
.…NaOH
…………………………………………………………………………………………………………………
..
…………………………………………………………………………………………………………………
.
…………………………………………………………………………………………………………………
…………………………………………………………………………………………………………………
.
………………………………………………………………………………………………………………..
18
…………………………………………………………………………………………………………………
.
Reacting metals with water
Setting the scene
When metals react with water they form an oxide or hydroxide, some produce
hydrogen. But not all metals react with water.
You will use the signs of a reaction to identify which metals react more readily, and
which react least readily.
Aims - react four different metals with water to decide which react most
vigorously
make observations of the reactions to decide how vigorously the reactions are
occurring.
Safety
Wear eye protection throughout the practical and wash spills off skin immediately.
Take care when handling test tubes as they can become hot and bubble during the
experiment.
Equipment and materials
eye protection, , test tubes, pieces of: zinc, lead, iron, magnesium ribbon, test-tube
rack, copper sulphate solution
Method
1 Put 2cm of water into a test tube. Label the tube magnesium.
2 Place a small piece of magnesium ribbon into the water.
4 Wait for a few minutes and draw what happens - draw how many bubbles you see.
5. Leave the tube to see if anything happens.
5 Repeat the method using zinc, lead, and iron. Label each tube with the metal it has in it.
6 leave the tubes until next lesson to see how they have changed
Results – draw what happens:
19
Metals Observations
Magnesium
Zinc
Iron
Lead
Questions/Prove-it tasks
1. Describe what you might see if a reaction has happened. Challenge
…………………………………………………………………………………………………………….
…………………………………………………………………………………………………………….
2. a) List the four metals in order of increasing reactivity with the water. Put 1 for the most
reactive, 2 for the second most reactive and so on. Extra challenge.
Magnesium ………………….
Lead ………………….
Iron ………………….
Zinc ………………….
Mg Magnesium Zn Zinc Fe Iron Pb Lead
20
b) Explain how you decided the order they should be in.
E.g. I chose magnesium as …………………………………………………………………………………………………..
……………………………………………………………………………………………………………………………………………….
3. How you can find out if you have produced hydrogen gas. Super challenge.
……………………………………………………………………………………………………………………………………………….
……………………………………………………………………………………………………………………………………………….
……………………………………………………………………………………………………………………………………………….
……………………………………………………………………………………………………………………………………………….
4. Explain what could you do to stop a metal reacting with water? Super challenge +.
……………………………………………………………………………………………………………………………………………….
……………………………………………………………………………………………………………………………………………….
……………………………………………………………………………………………………………………………………………….
……………………………………………………………………………………………………………………………………………….
……………………………………………………………………………………………………………………………………………….
……………………………………………………………………………………………………………………………………………….
……………………………………………………………………………………………………………………………………………….
……………………………………………………………………………………………………………………………………………….
Metal corrosion oxygen oxide paint grease anodised
Galvonised sacrificial protection
What have you learned this lesson?
This lesson I learned about:
………………………………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………………………………
21
CWK What is a displacement reaction? …………/………/…………………..
A. A displacement reaction is
when a ………………………… reactive
metal displaces (pushes off) a
less ………………………………… metal.
B. State why copper cannot displace
magnesium in magnesium sulfate
solution.
……………………………………………………….
…………………………………………………………
In a displacement reaction a
……………….
Reactive metal pushes out a
……………….
Reactive metals from its compound.
For example ………………………. displaces
………………………………….. from
……………………….. oxide.
Developing Secure Extending
C2 3.4
Metal displacement
reactions
I can state which metal is
more reactive in a pair of
named metals.
I can predict if a given
pair of substances will
undergo displacement.
I can explain why
displacement reactions
are predicted to occur or
not occur.
I can state where
different metals are
found in the reactivity
series.
I can use the reactivity
series to explain
displacement reactions.
I can use particle models
and diagrams to
represent displacement
reactions.
Key words
more less reactive metal solution compound oxide aluminium iron
22
Will a displacement reaction occur?
Setting the scene
The reactivity series lists metals in order of how reactive they are. More reactive metals are
able to displace less reactive metals from their compounds. This is a displacement reaction.
Safety
Wear chemical splash-proof eye protection throughout the practical activity.
If any chemicals get onto your skin, wash these off immediately and inform
your teacher.
Magnesium is flammable. Keep it away from naked flames.
Lead foil is toxic and is hazardous to the environment. Dispose of it as directed by your
teacher.
Zinc nitrate is harmful and oxidising. Keep this away from sources of heat and wash any
spills off your skin immediately.
Magnesium nitrate is oxidising.
Copper nitrate is harmful.
Lead nitrate solution is toxic.
Equipment and materials
eye protection [goggles], magnesium pieces, zinc pieces, copper pieces, lead pieces,
zinc nitrate solution, magnesium nitrate solution, copper nitrate solution, lead nitrate
solution, test tubes or spotting tile, test-tube rack, pipettes
Hypothesis
Which of the following statements describes what happens if a displacement reaction
takes place?
a A less reactive metal will displace a more reactive metal from its compound.
b A more reactive metal will displace a less reactive metal from its compound.
Method
1 Place a small piece of your first metal into four separate test tubes.
2 Add 1 cm3 of magnesium nitrate solution to one of the test tubes using a dropping pipette.
Record your observations.
3 Repeat Step 2 using zinc nitrate, copper nitrate, and lead nitrate, using a clean test
tube containing a fresh piece of metal and a clean pipette each time.
4 Now repeat Steps 1–3 for zinc, copper, and lead.
23
5 Fill in the table below to show whether a displacement reaction happened for each metal–
metal compound combination.
Use ticks to show pairs that had a displacement reaction and crosses to show those that
did not react.
Substance magnesium zinc copper lead
magnesium nitrate x
zinc nitrate
x
copper nitrate
x
lead nitrate
x
6 Explain why it is not necessary to react a metal with a solution of its own compounds. For
example, why is it not necessary to react copper with copper nitrate?
24
7 Write a word equation for each of the displacement reactions you observed occurring.
Example:
Magnesium + zinc nitrate magnesium nitrate + zinc
Magnesium + ……………………. nitrate magnesium nitrate + …………………
Magnesium + ……………………. nitrate magnesium nitrate + …………………
Zinc + ……………………. nitrate ……………………………… nitrate + …………………
Extension
1 Explain, using particle diagrams, what happens during a displacement reaction.
25
2 Write a balanced formula equation for each displacement reaction you have
identified in Question 4 above. Include state symbols in your equation.
Choose from the following list of possible chemical formulae:
Mg Mn Zr Zn Co Cu Pb Ph
Mg(NO3)2 Mn(NO3)2 Zr(NO3)4 Zn(NO3)2 Co(NO3)2
Cu(NO2)2 Pb(NO3)2 Pb3(PO4)2
……………………….. + ………………………… …………………………………………….. + ……………………………….
……………………….. + ………………………… …………………………………………….. + ……………………………….
……………………….. + ………………………… …………………………………………….. + ……………………………….
……………………….. + ………………………… …………………………………………….. + ……………………………….
……………………….. + ………………………… …………………………………………….. + ……………………………….
……………………….. + ………………………… …………………………………………….. + ……………………………….
26
Summary questions/Prove it tasks
a) React yes/no.
Because …………………………………………………………
………………………………………………………………………….
b) React yes/no.
Because …………………………………………………………
………………………………………………………………………….
c) React yes/no.
Because …………………………………………………………
………………………………………………………………………….
a) React yes/no.
Because …………………………………………………………
………………………………………………………………………….
27
CWK How are metals extracted from their ores ? …………/………/…………………..
A. An ore is a ………………………… that
you can extract a
………………………………. from.
B. Describe two stages in
extracting a metal from its
ore.
1. ……………………………………………………………
………………………………………………………………..
………………………………………………………………..
2. ……………………………………………………………
………………………………………………………………..
………………………………………………………………..
………………………………………………………………..
1. Underline the correct word and
cross-out the incorrect word.
……………………………………………………………………….
C2 3.5
Extracting metals
I can state where carbon
is found in the reactivity
series.
I can use the reactivity
series to decide which
metals can be extracted
from their ores by
heating with carbon.
I can explain why metals
can be extracted using
carbon, using the idea of
displacement.
I can calculate the
percentage of waste
material in a metal ore.
I can calculate the
amounts of metals in
ores.
I can convert amounts of
metals within ores from
masses to percentages,
or vice versa.
Key words rock metal separate oxide ore chemical charcoal carbon dioxide
28
How were metals extracted in the past?
Setting the scene
Many metals can be extracted from their ores. Ores are compounds that contain metals
combined with other elements. Metals such as iron have been used for many
thousands of years but how did people first get to this metal?
Aims
In this activity you will:
look at an early method for extracting iron from iron ore
use your knowledge of extracting metals to explain why this method works.
You will be working scientifically to:
present explanations of data.
Task
In Europe, around 900 BC, iron could be extracted using the following method. Read
the method and then answer the questions below.
29
Questions
1 Write the name that would be given to the rocks described in Step 1 of the method.
2 Suggest why wood or charcoal needs to be added to the fire or oven.
3 Write a word equation to represent the reaction that is happening in the above
method. Assume the iron ore is iron oxide only.
4 Use your knowledge of the reactivity series to explain why the above method could
be used to extract iron but not aluminium.
30
31
Extension
1 Write a formula equation to represent the extraction of iron described above.
Assume the formula for iron oxide is FeO. Include state symbols in your equation.
2 Suggest why iron artefacts, such as jewellery, appeared much later in history than those made
from gold but much earlier than those made from aluminium.
Hint: you may use the reactivity series to help you.
3 Sadie has 10 g of brucite and 50 g of dolomite, which are both magnesium ores.
If brucite contains 41 % magnesium by mass and dolomite contains 13 % magnesium
by mass, which sample will give Sadie more pure magnesium? Show your working.
32
CWK What are ceramics and why are they useful? …………/………/…………………..
Lesson Developing Secure Extending
C2 3.6
Ceramics
I can list the properties
of ceramics.
I can explain ceramic
properties.
I can distinguish between
chemical and physical
properties of ceramics.
I can list some uses of
ceramics.
I can explain why
properties of ceramics
make them suitable for
their uses.
I can justify why possible
ceramics are identified
from data about material
properties.
A. A ceramic material is a
…………………………………….. They include
……………………………… silicates, metal
…………………. , metal carbides and metal
……………………………………….
Examples are ………………………….. and bricks.
B. Four properties of ceramics are:
1. …………………………………………………………..
……………………………………………………………..
2. …………………………………………………………..
……………………………………………………………..
3. …………………………………………………………..
……………………………………………………………..
4. …………………………………………………………..
……………………………………………………………..
Key words compound metal nitrides pottery oxides bricks hard brittle stiff solid strong insulators
33
C. List three uses of ceramics
1. …………………………………………………………..
……………………………………………………………..
2. …………………………………………………………..
……………………………………………………………..
3. …………………………………………………………..
……………………………………………………………..
Complete the paragraph
........................................................................................................
........................................................................................................
........................................................................................................
........................................................................................................
........................................................................................................
........................................................................................................
34
Comparing ceramic strength 1 Which three ceramics will you test?
1
2
3
List of apparatus available: eye protection, clamp stand, masses of various sizes
ceramic samples, for example, dinner plates, roof tiles
What method will you use?
How can you use the apparatus above to design an experiment that will test the strength of
different ceramics?
Hint: could you hang masses from the ceramics, or pile them on top of the ceramics?
Write a step-by-step set of instructions in the space below.
Make sure you are only changing the type of ceramic being tested each time you do the
investigation.
1
2
3
4
5
6
7
35
4 How will you stay safe during your practical?
Fill in the risk assessment table below. Include other ideas you may have in the table.
Risk Likelihood of this happening How can we minimise this risk?
example:
dropping heavy
masses
unlikely
Ensure that masses are carried
with two hands and keep masses on top of tables where possible.
broken ceramic
clamp stands toppling
Results
Complete the results table below. The final column has been left blank for you to write
down the results of what you will be measuring.
Ceramic Description
36
Questions
1 Give the name of the independent variable in your investigation.
2 Give the name of the dependent variable in your investigation.
3 Explain how your method keeps the investigation fair.
4 Suggest any problems there may be in keeping your investigation fair.
Extension
1 Investigations should be valid. This means that they should measure, or find out about, what
they were meant to. Explain how your investigation is valid in measuring the strength of the
ceramic material.
37
Prove it:
What have you learned this lesson?
This lesson I learned about:
………………………………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………………………………
38
CWK What are polymers and why are they useful? …………/………/…………………..
A. A polymer is a substance
with very long ……………………………….
A polymer has …………………………
Groups of ……………………………
repeated many ………………….
B. Give an example of a polymer and one of it uses.
Polymer ……………………………………
Use ………………………………………….
Lesson Developing Secure Extending
C2 3.7
Polymers
I can state the definition
of a polymer.
I can describe polymer
properties.
I can explain properties
of different polymers.
I can state some uses of
polymers.
I can explain how
polymer properties
make them suitable for
their uses.
I can compare properties
of different polymers.
Key words molecules identical atoms groups wool jumpers cotton rubber polythene
39
c. Describe why low-density poly(ethane)
makes good carrier bags.
…………………………………………………………………………………
.
…………………………………………………………………………………
.
…………………………………………………………………………………
.
…………………………………………………………………………………
.
…………………………………………………………………………………
.
…………………………………………………………………………………
.
Complete the passage:
40
Ch
oo
se a
Q
41
42
Choosing suitable polymers
Setting the scene
Polymers are very long molecules made of identical repeating groups of atoms.
Different polymers contain different groups of atoms. The different groups give
polymers very different properties. This means polymers can be designed to have
properties that make them good for particular uses.
Aims
In this activity you will:
3 look at some information about different polymers
4 use this information to decide which jobs they can be used for.
You will be working scientifically to:
5 interpret data to draw conclusions
6 make predictions using your scientific knowledge
7 present explanations of data.
Task
Look through the table below about six different polymers. Use this information to fill in the grid
underneath, deciding which polymer is the most suitable for the different uses, and explaining
your answer.
Polymer Strength
Does it
conduct electricity?
Does it absorb water/
moisture?
What happens
when the polymer is
heated?
Cost to make (£
per square
metre)
Does it decay?
A very weak no no nothing 0.01 no
B very strong no no nothing 7.50 no
C strong no no it shrinks 0.05 yes, after
1 year
D strong no yes it burns 3.50 no
E weak no no nothing 0.02 yes, after
6 months
F weak yes no nothing 10.00 no
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Use Suitable polymer Reason for choice
t-shirt or top for a
marathon runner
disposable drinks cup
buoy
(floating marker in
the sea)
computer circuit
components
carrier bag
cling film
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Questions
1 Describe the differences between a synthetic and a natural polymer.
2 Suggest which two polymers above may be considered environmentally friendly.
Explain your answer.
Extension
Molecules that join to form polymers are produced from crude oil. Using this
information and your knowledge of fossil fuels, state three advantages and
three disadvantages of using polymers. Explain your answer.
What have you learned this lesson?
This lesson I learned about:
………………………………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………………………………
CWK What are composites and why are they useful? …………/………/…………………..
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A. A composite material is a
………………………………………………… of different
materials. Each material has different
…………………………………………………….
An example of a composite material is
……………………………………………………..
B. Two material in carbon-fibre-reinforced
plastic are ……………………………………………….
and ……………………………………………………………….
Lesson Developing Secure Extending
C2 3.8 Composite
s
I can state some
properties of composite
materials.
I can describe
composite properties.
I can explain composite
properties.
I can state some uses of
composite materials.
I can explain why
composite properties
make them suitable for
their uses.
I can suggest advantages
and disadvantages of
composite properties.
Key words mixture properties polymer carbon fibres glue-like density rust strong layers
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C. Name two material in glass-fibre-
reinforced aluminium.
1. …………………………………………………..
2. ……………………………………………………
Summary/Prove it
Underline the correct word and cross out
the incorrect word (use pencil first).
……………………………………………………………………………………. ……………………………………………………………………………………. ……………………………………………………………………………………. ……………………………………………………………………………………. ……………………………………………………………………………………. ……………………………………………………………………………………. …………………………………………………………………………………….
……………………………………………………………………………………. ……………………………………………………………………………………. ……………………………………………………………………………………. ……………………………………………………………………………………. ……………………………………………………………………………………. ……………………………………………………………………………………. ……………………………………………………………………………………. ……………………………………………………………………………………. …………………………………………………………………………………….
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……………………………………………………………………………………. ……………………………………………………………………………………. ……………………………………………………………………………………. …………………………………………………………………………………….
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Concrete properties
Setting the scene
Nisha has been finding out about the strength of concrete. Depending on how it is made, its
strength can vary, which means it can be used for lots of different purposes. She made concrete
by mixing 100 g of cement with water and a mixture called aggregate. She used different
amounts of aggregate each time and then tested the strength of the concrete.
Aims
In this activity you will:
8 use Nisha’s results to discover what she has found out about the strength of
concrete.
You will be working scientifically to:
9 present her data in an appropriate graph
10 interpret the data to identify patterns and draw conclusions
11 come up with some further questions from the results.
Task
Plot a suitable graph of Nisha’s results shown in the table and answer the questions below.
Amount of aggregate material added (g) Strength of concrete (N/mm2)
400 35
450 25
600 20
800 10
1000 7.5
Questions
1 Describe the pattern shown in the strength of concrete in Nisha’s results.
Use the data to explain your answer.
As more aggregate material is added to cement mix
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2 Reinforced concrete consists of steel bars with concrete around them. Using your knowledge of
composites, explain why reinforced concrete is preferable to normal concrete in the
construction of a new building.
Extension
1 Use your graph to suggest the strength of a concrete mixture that is made using 1200 g of
aggregate material. Show your working.
2 Identify whether cement or aggregate material is responsible for the strength of concrete using
your graph. Explain your answer.
3 Aggregate material can contain different amounts of sand and coarse or fine materials.
Different manufacturers will sell different compositions of aggregate material. This means they
may contain different amounts of sand or gravel, for example. Suggest a further investigation
Nisha may wish to carry out into the strength of concrete.
You must identify the independent, dependent, and at least two control variables.
What have you learned this lesson?
This lesson I learned about:
………………………………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………………………………
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Glossary
Key word Definition
carbon fibre A material made of thin tubes of carbon.
ceramic A compound such as a metal silicate or oxide that is hard,
strong, and has a high melting point.
composite A mixture of materials with properties that are a combination
of those of the materials in it.
displace A more reactive metal displaces – or pushes out – a less
reactive metal from its compound.
displacement reaction In a displacement reaction, a more reactive metal displaces
– or pushes out – a less reactive metal from its compound.
metal
Elements on the left of the stepped line of the Periodic Table.
Most elements are metals. They are good conductors of
energy and electricity.
natural polymer Polymers made by plants and animals, including wool,
cotton, and rubber.
ore A rock that you can extract a metal from.
polymer A substance made up of very long molecules.
reactive A substance is reactive if it reacts vigorously with substances
such as dilute acids and water.
reactivity series A list of metals in order of how vigorously they react.
state symbol
A state symbol gives the state of a substance in a chemical
equation. (s) means solid, (l) means liquid, (g) means gas,
and (aq) means dissolved in water.
synthetic polymer A substance made up of very long molecules that does not
occur naturally.
thermite reaction Reaction of aluminium with iron oxide to make aluminium
oxide and iron.
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