The British School of Bahrain Chemistry Department9E+Workbook.pdf · The British School of Bahrain...

The British School of Bahrain

Chemistry Department

Year 9 Workbook

9E Reactions of Metals and Metal Compounds

Name

Form

2

*P40126A0228*

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258 © Pearson Education Limited 2002Exploring Science for QCA Copymaster File 9

9Ea/3 What do we usemetals for?

9

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a

Name Class

The first column shows some uses of different metals. Fill in the names of themetals using names from the Metals list at the bottom of the page.

Each metal is used for a different reason. Draw lines to match up the uses and the reasons. Some metals are used for more than one thing. Fill in the gaps usingwords from the Uses list at the bottom of the page.

Metals and their uses Reasons

because it can be made into

is used to coat cans foil and it is light.

because it is a good conductor

is used for sweet wrappers. of electricity and can be bent.

It is also used for

because it does not rust easily.

is used in electrical cables.

It is also used for

_________________

because it is a metal which is

is used for jewellery. liquid.

It is also used for

_________________

_________________ because it is shiny, looks good

is used for drain covers. and lasts a long time. It is also

It is also used for a good conductor of electricity.

_________________

_________________

can be used in because it is strong and cheap.

thermometers

knowledgeS

Metals: aluminium copper gold iron mercury tinUses: aeroplanes bridges headphone connections water pipes


9Ea/5 Metals with amemory

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a

literacy, knowledgeS

If you heat a metal it expands, but it does not usually change shape unless it melts.Shape memory alloys (SMAs) are special alloys that change shape when they are heated.

An alloy is a mixture of different metals. A shape memory alloy can be made into aparticular shape, and allowed to cool. When it is cool it can be deformed (bent) into adifferent shape. It will keep this new shape as long as it stays below its ‘transformationtemperature’. If it is heated to a temperature above its transformation temperature, it will change back into its original shape. The alloy can exert a force when it changes shape.

The first time a shape memory change was observed was in 1932, in an alloy of goldand cadmium. However, the change was very small, and it was not until a muchbigger effect was seen in a nickel-titanium alloy in 1962 that people began to do muchmore research into SMAs, and try to find some uses. Today, the most common SMAsare NiTi alloys, and alloys of copper such as CuZnAl and CuAlNi. NiTi alloys are moreexpensive, but they can exert bigger forces when they change shape, and they arevery resistant to corrosion. Copper SMAs are cheaper and easier to make into therequired shapes, but are not as resistant to corrosion.

NiTi alloys can be used in medical applications. One such application is a blood clotfilter. A NiTi wire is made in a shape that will stay inside a vein and filter passingblood clots. The wire is cooled, and bent so that it can be inserted easily into the vein. When it gets inside the body, heat from the body makes it change back to itsoriginal shape.

CuZnAl SMAs can be used in fire safety valves, where the SMA changes shape and cuts off the supply of toxic or flammable gases if a fire occurs. SMAs can also be heated using an electric current. One application of this is in satellite release bolts, which have to release a satellite from a rocket at the right point in the launch sequence.

1 What is a shape memory alloy?

2 a Name two copper based SMAs.

b Which elements does each SMA contain?

3 Nitinol is the name for a nickel-titanium alloy. Make up a brand name for aCuAlNi alloy.

4 What does ‘transformation temperature’ mean?

5 Why do you think there was not much interest in SMAs until 1962?

6 Describe one medical use of SMAs.

7 Why are NiTi SMAs more suitable than the copper based alloys for medicalapplications?

8 Why would an SMA have to be heated by an electric current to release asatellite from a rocket?

9 What is the difference between an alloy and a compound?

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9Eb/1 Making hydrogen 1

9

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b

Sulphuric�acid

Zinc

Label the parts of the first diagram using the words in the box.

PApparatus� Conical flask � Water� Delivery tube and bung � Dilute hydrochloric acid� Water trough � Zinc metal� Beehive shelf � Eye protection� Boiling tube � Splint� Tube rack

�Wear eye

protection.

beehive shelf delivery tube conical flask water trough boiling tube

Method

1 Fill the boiling tube with water and place it over the end of the delivery tubeso that it is set up as shown in the drawing.

4 When the tube is full of gas, place a bung in theend and then remove the tube from the trough ofwater and place it in a rack.

5 Light a splint. Remove the bung from the boilingtube and place the burning splint into the top ofthe boiling tube.

6 If the gas explodes with a squeaky pop, it ishydrogen.

Name Class

2 Add the acid to the zinc in the conical flask andpush the bung firmly into place.

3 Hold the boiling tube over the end of the deliverytube until it is full of gas.

observingS


9Eb/3 Fizzing metals

9

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b

knowledgeS

1 The diagram shows an experiment.

a Name the metal in this experiment.

b Name the acid in this experiment.

c How can you tell that a reaction is occurring?

d A gas is given off which produces a squeaky pop. Which gas is it? Choose from the following:

oxygen hydrogen nitrogen

carbon dioxide argon

e If you wanted to collect this gas, which of these sets of apparatus wouldyou use?

?

zinc

hydrochloric acid

f Explain how the apparatus that you have chosen works.

2 The reaction between zinc and hydrochloric acid produces a salt called zincchloride. If we had used sulphuric acid instead, the salt would be called zincsulphate. Copy and complete these word equations.

a zinc + hydrochloric acid → +

b zinc + → zinc sulphate +

c + hydrochloric acid → aluminium chloride +

d aluminium + sulphuric acid → +

3 Some metals are unreactive and will not react with acids. From this list,which metal would you not expect to react with acids?

zinc aluminium magnesium gold calcium

heat

A B

C

D


9Eb/5 Hydrogen

9

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b

Hydrogen is the lightest element. It isa gas at room temperature. Hydrogenis made up of molecules formed from two hydrogen atoms joinedtogether. We can represent this as:

knowledge, literacyS

Hydrogen gas is not found naturally in the air, but hydrogen atoms are found in morecompounds than any other element. These compounds include water (H2O). Water isthe most common compound on Earth and is essential for life.

When hydrogen burns in air, it reacts with oxygen and forms water:

H

nucleus

HH — HorH2

or

electron

hydrogen + oxygen → water

This reaction gives out a large amount of energy. If the reaction is not carefully controlled, the hydrogen and oxygen react explosively. We see this explosion on a small scale when we test a tube of hydrogen gas with a lighted splint.

The reaction between hydrogen and oxygen is used to power rockets and space craft. Hydrogen is now beginning to be used to power buses and cars. Special tanks store the hydrogen gas under pressure in the boot of the car. Great care must betaken when refuelling so that the risk of an explosion is reduced. The vehiclesproduce no pollution because the only waste product is water vapour!

The hydrogen mixes withoxygen from the air and burnswith a ‘squeaky pop’. This isthe test for hydrogen gas.

1 Hydrogen gas is not found naturally in the air. Why do you think this is?

2 The Head Teacher thinks that the ‘squeaky pop’ given off when a sample ofhydrogen burns is really an explosion and shouldn’t be allowed in the lab.What would you say to help the Head Teacher to understand why it is safe todo this test in science lessons?

3 Hydrogen is being used as a fuel in some road vehicles.

a Why must the gas be stored under pressure in the tanks?

b Write a word equation for the reaction that happens when hydrogen isused as a fuel.

c Write a symbol equation for this reaction.

4 Great care must be taken when refuelling a hydrogen-powered vehicle, tomake sure that there isn’t an explosion.

a What might cause an explosion?

b If you were the driver of a hydrogen-powered vehicle, what precautionswould you take when refuelling?

5 The R101 airship was filled with hydrogen gas.

a Why was hydrogen used?

b Why was this dangerous?

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9Eb/6 What would happen if …?

9

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b

Table of reactivity.

knowledgeS

For each of the following reactions, predict:

a whether there will be any reaction between the metal and the acid

b how fast that reaction will be

c what the products will be, writing a word and/or symbol equation for each reaction.

Use the table of reactivity to help you.

1 zinc + hydrochloric acid

2 zinc + sulphuric acid

3 magnesium + hydrochloric acid

4 gold + sulphuric acid

5 sodium + hydrochloric acid

6 copper + hydrochloric acid

7 lead + hydrochloric acid

8 iron + sulphuric acid

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Metal Reaction with acid

sodium reacts very vigorously

calcium

magnesium

aluminium

zinc

iron

lead slow reaction

copper no reaction

silver no reaction

gold no reaction

Reac

tions

bec

ome

mor

e vi

goro

us a

s yo

u go

up

the

tabl

e.


9Ec/1 Rocks and acid

9

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c

Acid rain corrodes rocks that contain carbonates. Your task is to find out which rockscontain carbonates by seeing which ones are affected by acid rain. You should set up a‘control’ experiment using water, so that you can check that any reaction is caused bythe acid and not just water.

observing, considering, evaluatingS

Method

1 Select your samples of rock. For each rock type you will need two pieces ofthe rock which are about the same size.

2 Place the rock samples into labelled Petri dishes.

3 Slowly add ‘acid rain’ to one piece of rock, drop by drop, until the rock isstanding in a small pool of acid.

4 Slowly add water to the second piece of rock, drop by drop in the same way,until the rock is standing in about the same amount of liquid.

5 Record your observations and then place the dishes in a safe place.

6 Examine the rocks at regular intervals during a week and record anydifferences between the two samples.

7 Collect the results of all the members of your class.

P Apparatus� Samples of rock (e.g. chalk, marble, Cotswold stone,

sandstone, granite, slate)� ‘Acid rain’ � Eye protection� Dropping pipettes � Water� Universal indicator � Petri dishes

�Wear eye

protection.

Considering your results/conclusions

1 Did any of your rock samples react with the acid when it was added?

2 Did any of your rock samples react with the water when it was added?

3 Did any of the rocks used by your class react straightaway? If so, which ones?

4 Which rocks reacted later?

5 What does this tell you about the effect of acid rain on different rocks?

6 What does this tell you about the effect of water on different rocks?

7 From your results, which rocks appeared to contain carbonates?

Evaluation8 If you wanted to build a house out of rock, which of these rocks would you use?

Why?

9 Did you carry out a fair test? How could you have improved your method?


9Ec/2 Carbonates and acid

9

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c

Many rocks contain carbonates. This experiment shows how carbonates react withdilute sulphuric acid.

Method

1 Place 10 cm3 of dilute sulphuric acid in a 100 cm3 beaker and measure the pHcarefully using a piece of indicator paper. Hold the paper using the forceps.

2 Add a spatula of powdered copper carbonate. Keep away from any sprayfrom the reaction. Record your observations.

3 Add some more copper carbonate and look carefully at the mixture. Keepadding small amounts of copper carbonate until there is no further reaction.

4 Does the test tube get hot?

5 Test the pH of the solution with indicator paper.

6 Repeat your experiment using either a different metal carbonate instead ofcopper carbonate, or a different dilute acid instead of dilute sulphuric acid.

P Apparatus� Copper carbonate powder � Boiling tubes � Dilute sulphuric acid � Bung� 100 cm3 beaker � Delivery tube� Universal indicator paper � Eye protection� Sodium carbonate powder � Limewater� Calcium carbonate powder � Dilute nitric acid� Dilute hydrochloric acid � Forceps� Spatula

�Wear eye

protection.

copper carbonate and dilute sulphuric acid

limewater

Recording your results

1 Write down what happened when you added the metal carbonate.

2 Write down the pH at the start and at the end of these experiments.

Considering your results/conclusions

3 a Did the pH of the liquid change during the reaction?

b What does this tell you about the reaction?

The experiment could be carried out using thisapparatus which allows the gas to be bubbledinto limewater.

4 If the limewater turns milky, which gas is released during the reaction?

5 Write a word equation for the reaction which has occurred between copper carbonate and dilute sulphuric acid.

6 Predict the names of the products formed for each of the reactions you carried out.

observing, consideringS


9

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c

9Ec/3 Calcium carbonate

The hardness of a sample of water can be tested by adding some soap and seeingwhether a lather is formed. Soft water lathers easily with soap, hard water does not.

The hardness of a sample of water can be measured by adding small amounts ofsoap solution to a fixed volume of water, until a stable lather is produced whenthe two are mixed. The more soap solution required to make the lather, theharder the water sample.

1 Plan and carry out an investigation to compare the hardness of three labelled water samples using this method (you might like to use variousbottled waters).

Hardness can be temporary or permanent. Temporary hardness is due to thepresence of calcium hydrogencarbonate in the water. This can be removed byboiling the water. Permanent hardness is caused by calcium sulphate andmagnesium sulphate and cannot be removed by boiling the water.

2 Plan an experiment to test your sample of water to find out whether thehardness in your samples of water is temporary or permanent. You may beable to carry out your experiment after your teacher has checked your plan.

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planning, observing, consideringS


9

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c

9Ec/4 Rocky equations!

Calcium carbonate is one of the most common minerals in the Earth’s crust. Rockssuch as chalk, limestone and marble are all mainly made from calcium carbonate.Calcium carbonate reacts with acids to give off carbon dioxide gas.

Coral and Simon did an experiment with three different types of rock. They added thesame amount of hydrochloric acid to three 10 g samples of rock. This is the apparatusthat they used:

knowledge, presenting, consideringS

Here are their results:

Time in seconds 0 10 20 30 40 50 60 70 80

volume of gas in cm3 (Rock A) 0 19 32 43 50 56 59 60 60

volume of gas in cm3 (Rock B) 0 0 0 0 0 0 0 0 0

volume of gas in cm3 (Rock C) 0 25 40 50 55 60 60 60 60

1 Plot these results on a piece of graph paper. Plot all three lines on the same graph. Use axes like this:

2 Which two rocks were carbonates? Explain your answer.

3 How would you test for carbon dioxide gas?

4 One of the rock samples was marble chips and the otherwas powdered chalk. Suggest which rock was powderedchalk. Explain your answer.

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marble chips

gas syringe

Time (s)

Vo

lum

e (c

m3)


9

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c

9Ec/5 International chemistry

The following passages have been taken from science textbooks. Read them carefully.

knowledgeS

1 What are the pages from these textbooks about? Summarise their contents ina few sentences.

2 Answer the questions contained in the French textbook.

3 What can you say about the answers to the questions in the German textbook.

4 Think about these textbooks from different countries. What do they teachyou about the language of science?

5 Write a scientific sentence which describes the reaction between coppercarbonate and sulphuric acid (forming copper sulphate, carbon dioxide andwater) so that it could be understood by a person who does not understandor speak any English.

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Passage 1

Quand on melange de l’acide sulfurique (H2SO4) avec du cuivre carbonate(CuCO3), le cuivre carbonate commence à pétiller. Il pétille parce que l’un desproduits de cette réaction est un gaz qui s’echappe. Ce gaz est du dioxide decarbone, qui est composè de carbone et d’oxygene. On note l’equation de la réaction entre l’acide sulfurique et le cuivre carbonate:

H2SO4 + CuCO3 → CuSO4 + CO2 + H2O

A Quel est le produit de la réaction entre MgCO3 et HCl?

B Quel acide réagirait avec MgCO3 pour produire MgSO4?

Passage 2

Wenn verdünnte Schwefelsäure(H2SO4) Kupferkarbonat (CuCO3) zugefügt wird,beginnt sie zu schäumen. Der Grund ist, dass eines der Reaktionsprodukte ein Gasist, welches entweicht. Dieses Gas ist Karbondioxyd, welches die Elemente Karbonund Sauerstoff enhält. Wir können die reaction zwischen Schwefelsäure undKupferkarbonat in der folgenden Gleichung erfassen:

H2SO4 + CuCO3 → CuSO4 + CO2 + H2O

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? A Was wird in einer Reaktion zwischen MgCO3 und HCl produziert?

B Welche Säure produziert MgSO4 wenn sie mit MgCO3 reagiert?


9

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c

9Ec/6 Reactions in symbolsSince atoms in a reaction cannot be destroyed, when we write a symbol equation we needto make sure we have the same number of each type of atom on each side of the equation.

For example, the following equation is not correct: it is unbalanced.

Zn + HCl → ZnCl2 + H2

The formula for zinc chloride is ZnCl2 so we cannot change that. The formula forhydrogen is H2 and we cannot change that. We can only put extra numbers in front ofthe formulae:

Zn + 2HCl → ZnCl2 + H2

The equation is now balanced.

The formulae for some compounds are given in the table. Note that some atoms arealways grouped together. This is shown by brackets. The small number after thebrackets shows how many of these groups you have. So (PO4)2 shows that you havetwo phosphate (PO4) groups – a total of two phosphorus atoms and eight oxygen atoms.

knowledgeS

1 What are the products of the reaction between a metal carbonate and an acid?

2 Use the formulae in the table to help you write balanced symbol equationsfor the following reactions. For each reaction, give the complete wordequation as well as the balanced symbol equation.

a copper carbonate + sulphuric acid

b magnesium carbonate + sulphuric acid

c calcium carbonate + hydrochloric acid

d magnesium carbonate + hydrochloric acid

e copper carbonate + nitric acid

f magnesium carbonate + nitric acid

g sodium hydrogencarbonate + hydrochloric acid

h sodium hydrogencarbonate + sulphuric acid

i magnesium carbonate + phosphoric acid

j sodium hydrogencarbonate + ethanoic acid

k calcium carbonate + phosphoric acid

l sodium hydrogencarbonate + stearic acid

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Name Formula Name Formula Name Formula

calcium chloride CaCl2 magnesium carbonate MgCO3 sodium chloride NaCl

calcium phosphate Ca3(PO4)2 magnesium chloride MgCl2 sodium ethanoate CH3COONa

copper carbonate CuCO3 magnesium nitrate Mg(NO3)2 sodium NaHCO3

copper nitrate Cu(NO3)2 magnesium phosphate Mg3(PO4)2hydrogencarbonate

copper sulphate CuSO4 magnesium sulphate MgSO4 sodium stearate CH3(CH2)16COONa

ethanoic acid (also CH3COOH nitric acid HNO3 sodium sulphate Na2SO4

called acetic acid) phosphoric acid H3PO4 stearic acid CH3(CH2)16COOH

hydrochloric acid HCI sulphuric acid H2SO4


9Ed/1 Making a salt –potassium chloride 1

9

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dRead the method for making a salt at the bottom of the page. Then answer thequestions before carrying out the experiment.

1 What will you use to measure out 25 cm3 of hydrochloric acid?

2 How will you measure out 2 cm3 of dilute potassium hydroxide solution?

3 What do you expect the pH of the solution in the beaker to be at the start of the experiment?

4 What do you think will happen to the pH as more potassium hydroxide is added to the beaker? Why?

5 How much dilute potassium hydroxide do you think you will need to add? Why?

6 Why does the volume of the liquid go down when we heat the evaporating basin?

7 What is the liquid which we are removing? Where does it go?

8 What are the crystals that form when the evaporating basin cools down?

9 Where have the crystals come from?

10 Write a word equation for the reaction which takes place in the beaker.

Method

1 Put 25 cm3 of dilute hydrochloric acid in a 100 cm3 beaker.

2 Add 2 cm3 of dilute potassium hydroxide solution and stir well.

3 Measure the pH of the mixture using universal indicatorpaper.

4 Repeat steps 2 and 3 until the mixture is no longer acidic.

5 Pour the mixture into an evaporating basin and heat themixture gently.

6 When about a third of the liquid is left, place the hotevaporating basin on a heat-proof mat to cool. Do notlet it boil dry or the hot crystals will spit out.

7 Examine the crystals of salt formed.

P Apparatus� Hydrochloric acid � 100 cm3 beaker� Potassium hydroxide � 50 cm3 measuring cylinder� Universal indicator � Evaporating basin

paper � Bunsen burner� 5 cm3 syringe � Tripod� Heatproof mat � Pipe-clay triangle� Forceps � Eye protection

�Wear eye

protection.

knowledge, observingS


9Ed/2 Making a salt –potassium chloride 2

9

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d1 Potassium chloride is formed when dilute potassium hydroxide solution is added to

dilute hydrochloric acid. Write a word equation for this reaction.

2 Will there be any acid left in the beaker at the end of the neutralisation reaction?

3 There are three methods which can be used to measure the pH of the solution.

a What are they?

b What are the advantages and disadvantages of using each method when makinga sample of a salt?

c Which method would you prefer to use in this experiment? Why?

Method

1 Carefully measure out 25 cm3 of dilute hydrochloric acid and place it in theconical flask.

2 If you are using indicator solution, add a few drops and record the result. Ifyou are using a pH probe or indicator papers, measure the pH and record it.

3 Set up a burette filled with dilute potassium hydroxide solution.

4 Slowly add 2 cm3 of the dilute potassium hydroxide solution, swirling thebeaker gently.

5 Measure the pH of the solution and record the result.

6 Repeat steps 4 and 5 until the acid has all been neutralised.

7 Record the volume of potassium hydroxide solution needed to just neutralisethe hydrochloric acid.

P Apparatus� Hydrochloric acid � Potassium hydroxide� 250 cm3 conical flask � Forceps� 50 cm3 measuring cylinder � Burette� Universal indicator paper � Eye protection

or solution or pH probe

�Wear eye

protection.

4 a If you used a pH probe or indicator paper, you may be able to separate the saltformed from the solution. How would you do this?

b If you used indicator solution, why would it be difficult to separate pure salt from the mixture?

observingS

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9Ed/3 Salts

Name Class

9

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d

knowledge, researchS

1 a For each of the salts listed below, work out what the name shows aboutthe chemicals which reacted together to form it.

Many different salts have been mentioned in this Unit.

b You may also have met the following salts. What do their names show?

Name of salt What the name shows

zinc chloride

zinc sulphate

copper chloride

copper sulphate

magnesium sulphate

sodium chloride

potassium chloride

potassium nitrate

Name of salt What the name shows

iron chloride

calcium chloride

calcium sulphate

calcium nitrate

copper nitrate

sodium nitrate

magnesium chloride

aluminium nitrate

silver nitrate

2 Research and write a report on the uses of one of the following salts:

sodium stearate calcium phosphatepotassium nitrate magnesium sulphatecopper sulphate silver nitrate

Use CD-ROMs, the internet and the library to help you in your research.


9Ed/6 Word equations formaking salts

Name Class

9

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d

A salt is formed when an acid reacts with an alkali. The first part of the name of thesalt comes from the name of the metal in the alkali. The second part of the namecomes from the name of the acid.

For example, when potassium sulphate is made:

The potassium comes from the potassium hydroxide; the sulphate comes from thesulphuric acid.

The word equation for this reaction is

potassium hydroxide + sulphuric acid → potassium sulphate + water

Different acids form different salts.

knowledgeS

chlorides are made from hydrochloric acid

sulphates are made from sulphuric acid

nitrates are made from nitric acid

Use the table to help you write word equations like the one above for thefollowing reactions:

1 Potassium hydroxide reacting with sulphuric acid.

+ → +

2 Potassium hydroxide reacting with nitric acid.

+ → +

3 Potassium hydroxide reacting with hydrochloric acid.

+ → +

4 Calcium hydroxide reacting with hydrochloric acid.

+ → +

5 Magnesium oxide reacting with hydrochloric acid.

+ → +

6 Calcium hydroxide reacting with sulphuric acid.

+ → +

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9Ed/7 Using salts

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dSalts are very useful chemicals. There are a large number of different salts which havemany different uses.

Look at these labels torn off packets and use the information to answer the questions below.

1 Name two ways that potassium nitrate can be used.

2 Name three elements that plants need for healthy growth.

3 a Write down two uses for copper sulphate.

b Copper sulphate can be made using a reaction between copper oxide andan acid. Which acid?

c Write a word equation for this reaction.

4 a Give two reasons for adding sodium chloride (common salt) to food.

b Suggest an acid and an alkali that could be reacted together to makesodium chloride.

c Write a word equation for this reaction.

d What is this sort of reaction called?

e What pH is a solution of sodium chloride in pure water?

5 When photographic film is exposed to light, the salt on the film breaksdown. What metal do you think is formed?

?

Bert’s Bacon is naturally

preserved usingsodium chloride.

Give your wood a shine!‘Stay Shiny’ varnish alsohelps to preserve woodbecause it containscopper sulphate.

THE CALCIUM PHOSPHATE

AND POTASSIUM NITRATE

IN ‘HAPPY-GRO’FERTILISER GIVE PLANTS

ALL THE NITROGEN,PHOSPHOROUS AND

POTASSIUM THEY NEED TO

GROW HEALTHY ROOTS,SHOOTS AND LEAVES.

This dye contains copper

sulphate and may stain skin.

Danger! This gunpowdercontains potassium nitrate and is highly explosive.

This photographic film is coatedwith silver nitrate and should bekept in a light-proof container until you are ready to use it.

❢ ❢

knowledge, literacyS


9Ed/8 Making copper sulphate

9

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dCopper sulphate is an example of a salt which is formed when an insoluble base reactswith an acid. This is a set of instructions for preparing copper sulphate (CuSO4) fromsulphuric acid and copper oxide.

� Add small amounts of solid copper oxide powder to 25 cm3 of dilute sulphuricacid, and stir.

� Keep adding powder slowly until some unreacted copper oxide remains at the bottom.

� Filter the solution to remove the unreacted copper oxide and transfer the filtrateinto an evaporating basin.

� Heat the contents of the evaporating basin gently until about a third of the waterhas evaporated.

� Leave the solution to cool and then examine the crystals which are formed.

1 Write a list of all the apparatus that would be needed to prepare coppersulphate crystals.

2 What safety precautions would you need to take if you were following theseinstructions?

3 Why was copper oxide added until some was left on the bottom of the beaker?

4 Why is it better to have copper oxide powder left in the beaker after thereaction, rather than having dilute sulphuric acid left behind?

5 Why was it necessary to filter the mixture before evaporating it?

6 Write word and symbol equations for the reaction that took place.

7 What would the copper sulphate crystals look like?

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knowledgeS


Page 1 of 2

9Ea

1 Compared to non-metals, metals are:

A good conductors of heat but notelectricity.

B good conductors of electricity but notheat.

C good conductors of both heat andelectricity.

D not good conductors.

2 Which list contains only magneticmaterials?

A magnesium, copper, gold

B aluminium, gold, iron

C iron, nickel, cobalt

D nickel, tin, lead

3 Which of these describes some propertiesof most metals?

A They ring when hit, are shiny and mostare solids.

B They are all liquids, have high meltingpoints and conduct electricity.

C They cannot be shaped or pulled intolong thin wires.

D They are all brittle and break when youtry to bend them or hit them.

4 Which of the following statements is true?

A Iron is used to make planes because itis very strong and light.

B Aluminium is used to make jewellerybecause it is light, strong and shiny.

C Gold is used to make buildings becauseit is very cheap and gold is a verycommon metal.

D Copper is used to make electrical wiresbecause it conducts electricity well andcan be stretched.

On your answer sheet, write in or circle the correct letter for each question.

9

E

9E Quick Quiz

9Eb

1 When some acid is put onto a piece ofmetal:

A there is always a reaction which burnsa hole in the metal.

B there is never a reaction.

C some metals will react with the acidand produce bubbles of gas.

D there is always a reaction, whichproduces a powder.

2 Which of the following is the correct wayto test for hydrogen gas?

A Bubble the gas through limewater.

B Bubble the gas through universalindicator solution.

C Put a glowing splint into a tube of thegas (the splint will burn brightly).

D Put a burning splint into a tube of thegas (the gas will explode with asqueaky pop).

3 If an acid reacts with a metal, the productsare:

A a salt and water.

B a salt and hydrogen gas.

C only hydrogen gas.

D a salt, water and carbon dioxide.

4 Which of the following is not needed tomake a prediction about the products of areaction between a metal and an acid?

A general information about the reactionsbetween metals and acids

B information about the properties of themetal

C the name of the metal used

D the name of the acid used


Page 1 of 2

9E Summary Sheets

The properties of a substance are the words that we use to describe it, ormeasurements that we can make on it. Metals and non-metals have differentproperties.

9

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Metals … Non-metals …

are good conductors of heat and electricity are poor conductors of heat and electricity (except for carbon in the form of graphite which conducts electricity)

are shiny are dull

are solids, often with high melting points are mostly solids or gases(except for mercury)

are found on the left-hand side of the Periodic Table are found on the right-hand side of the Periodic Table

are sometimes magnetic – three metals are magnetic are never magnetic(iron, cobalt and nickel)

form basic oxides form acidic oxides

are rigid when thick and bendy when thin are brittle

can be hammered into shape cannot be hammered into shape – the solid ones break

Reactions of metals and metal compounds

Using metalsMetals and non-metals have different uses because of their different properties.

Metals and acidsMany metals react with acids. Some unreactive metals will only react very slowly withstrong acids, some will not react at all. Some metals are more reactive and explodewhen added to acid.

When a metal reacts with an acid, hydrogen gas is given off. The reaction alsoproduces a compound called a salt.

There are three main types of salt:

Chlorides are made when hydrochloric acid is used.

Sulphates are made when sulphuric acid is used.

Nitrates are made when nitric acid is used.

Aluminium is used for power linesbecause it is light and it is a goodconductor of electricity.

Iron and steel are used for bridgesbecause they are strong and cheap.

Gold is used for jewellery because itdoes not corrode and looks nice.


9E Target Sheet

Topic Targets Before the unit I have learned this I have revised this9Ea 1 Know how good metals and

non-metals are at conducting heat and electricity.

2 Know which metals are magnetic.

3 Know some of the other properties of metals and non-metals.

4 Know that different metals have different uses because of their properties.

9Eb 1 Know what happens when metals and acids react.

2 Know how to test for hydrogen safely.

3 Know how to write a general word equation for the reaction between a metal and an acid.

4 Know how to predict the name of the product formed when a metal and an acid react.

9Ec 1 Know what happens when rocks and acids react.

2 Know how to test for carbon dioxide.

3 Know how to write a word equation for the reaction between an acid and a metal carbonate.

4 Know how to tell if a chemical reaction has taken place.

9Ed 1 Know what neutralisation is.

2 Know the general word equation for the reaction between an acid and a base.

3 Know how to write a word equation for the reaction between an acid and a metal oxide.

4 Know that there are many different salts and know some of their uses.

9

E

Name Class


9E Word Sheets

9

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Word Pronunciation Meaning

metals Elements that are shiny, conduct heat and electricity well and often have high meltingand boiling points.

non-metals Elements that are not shiny, and do not conduct heat and electricity well. They often have low melting and boiling points. The solid ones are brittle.

property Something that is used to describe how a material behaves and what it is like.Hardness is a property of some solids.

9Ea – Spot the difference


salts Compounds made in some reactions involving acids. They have a metal part and a non-metal part. The non-metal part is usually chloride, sulphate or nitrate (e.g. potassium sulphate).

9Eb – Metallic fizz


weathered Broken down by chemical or physical changes.

9Ec – More bubbles


base A chemical which reacts with an acid to form a salt.

neutralisation Mixing an acid and a base together to make a solution with a pH of 7.

9Ed – Metal oxides and acids/All about salts

Word sheets that include new words from the ‘Focus on:’ pages are available on theExploring Science website.


Page 1 of 2

9E Summary Sheets

The properties of a substance are the words that we use to describe it, ormeasurements that we can make on it. Metals and non-metals have differentproperties.

9

E

Metals … Non-metals …

are good conductors of heat and electricity are poor conductors of heat and electricity (except for carbon in the form of graphite which conducts electricity)

are shiny are dull

are solids, often with high melting points are mostly solids or gases(except for mercury)

are found on the left-hand side of the Periodic Table are found on the right-hand side of the Periodic Table

are sometimes magnetic – three metals are magnetic are never magnetic(iron, cobalt and nickel)

form basic oxides form acidic oxides

are rigid when thick and bendy when thin are brittle

can be hammered into shape cannot be hammered into shape – the solid ones break

Reactions of metals and metal compounds

Using metalsMetals and non-metals have different uses because of their different properties.

Metals and acidsMany metals react with acids. Some unreactive metals will only react very slowly withstrong acids, some will not react at all. Some metals are more reactive and explodewhen added to acid.

When a metal reacts with an acid, hydrogen gas is given off. The reaction alsoproduces a compound called a salt.

There are three main types of salt:

Chlorides are made when hydrochloric acid is used.

Sulphates are made when sulphuric acid is used.

Nitrates are made when nitric acid is used.

Aluminium is used for power linesbecause it is light and it is a goodconductor of electricity.

Iron and steel are used for bridgesbecause they are strong and cheap.

Gold is used for jewellery because itdoes not corrode and looks nice.

Page 2 of 2


9E Summary Sheets (continued)

The general equation is:

acid + metal → salt + hydrogen

For example:

hydrochloric acid + zinc → zinc chloride + hydrogen

We can test for hydrogen by putting a burning splint into a test tube of gas. Ifhydrogen is present, it will explode with a squeaky ‘pop’.

BasesBases are compounds which react with acids. All metal oxides, metal hydroxidesand metal carbonates are bases. Bases which dissolve in water are called alkalis(e.g. sodium hydroxide).

Metal oxides and hydroxides and acidsA metal oxide or a metal hydroxide reacts with an acid to form water and a salt. Thisreaction is called neutralisation.


acid + metal oxide → salt + water(or hydroxide)

For example:

hydrochloric acid + potassium hydroxide → potassium chloride + water

sulphuric acid + copper oxide → copper sulphate + water

We can check to see if neutralisation has occurred using universal indicator. The pH ofthe solution gets closer to neutral (pH7).

Metal carbonates and acidsA metal carbonate will also neutralise an acid. This time the products are a salt,carbon dioxide and water.


acid + metal carbonate → salt + carbon dioxide + water

For example:

sulphuric acid + copper carbonate → copper sulphate + carbon dioxide + water

We can test for carbon dioxide using limewater. Limewater goes milky if carbondioxide is bubbled through it.

Some rocks, like limestone, contain calcium carbonate. The rock fizzes when an acid isadded and some of the rock is worn away. The rock is weathered.

9

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Page 1 of 2

9Ea

1 Compared to non-metals, metals are:

A good conductors of heat but notelectricity.

B good conductors of electricity but notheat.

C good conductors of both heat andelectricity.

D not good conductors.

2 Which list contains only magneticmaterials?

A magnesium, copper, gold

B aluminium, gold, iron

C iron, nickel, cobalt

D nickel, tin, lead

3 Which of these describes some propertiesof most metals?

A They ring when hit, are shiny and mostare solids.

B They are all liquids, have high meltingpoints and conduct electricity.

C They cannot be shaped or pulled intolong thin wires.

D They are all brittle and break when youtry to bend them or hit them.

4 Which of the following statements is true?

A Iron is used to make planes because itis very strong and light.

B Aluminium is used to make jewellerybecause it is light, strong and shiny.

C Gold is used to make buildings becauseit is very cheap and gold is a verycommon metal.

D Copper is used to make electrical wiresbecause it conducts electricity well andcan be stretched.

On your answer sheet, write in or circle the correct letter for each question.

9

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9E Quick Quiz

9Eb

1 When some acid is put onto a piece ofmetal:

A there is always a reaction which burnsa hole in the metal.

B there is never a reaction.

C some metals will react with the acidand produce bubbles of gas.

D there is always a reaction, whichproduces a powder.

2 Which of the following is the correct wayto test for hydrogen gas?

A Bubble the gas through limewater.

B Bubble the gas through universalindicator solution.

C Put a glowing splint into a tube of thegas (the splint will burn brightly).

D Put a burning splint into a tube of thegas (the gas will explode with asqueaky pop).

3 If an acid reacts with a metal, the productsare:

A a salt and water.

B a salt and hydrogen gas.

C only hydrogen gas.

D a salt, water and carbon dioxide.

4 Which of the following is not needed tomake a prediction about the products of areaction between a metal and an acid?

A general information about the reactionsbetween metals and acids

B information about the properties of themetal

C the name of the metal used

D the name of the acid used

Page 2 of 2


9E Quick Quiz (continued)

9

E9Ec

1 When some acid is put onto a piece ofrock:

A it always reacts and gives off a gas.

B it reacts if the rock contains acarbonate.

C it always reacts explosively and shattersthe rock.

D it won’t react.

2 The best test for carbon dioxide uses:

A universal indicator solution.

B a burning splint.

C litmus paper.

D limewater.

3 When an acid reacts with a metalcarbonate, the products are:

A the metal and carbon dioxide.

B a salt and water.

C carbon dioxide, water and a salt.

D the metal, a salt and water.

4 Which of these is not a sign that areaction has taken place?

A The substance catches fire.

B The substance has changed from a solidto a liquid.

C A gas is given off.

D There is an explosion.

9Ed

1 A neutral solution is made when:

A two acids are added together.

B an acid and an alkali are addedtogether.

C water is added to an acid.

D water is added to an alkali.

2 When an acid and an alkali react together:

A a salt and water are both produced.

B only a salt is produced.

C a metal is formed.

D a gas is given off.

3 Which of these word equations is correct?

A copper oxide + hydrochloric acid →copper sulphate + water

B copper oxide + hydrochloric acid →copper chloride + carbon dioxide + water

C copper oxide + hydrochloric acid →copper chloride + hydrogen

D copper oxide + hydrochloric acid →copper chloride + water

4 Which of these is not a salt?

A magnesium sulphate

B iron sulphide

C tin chloride

D zinc nitrate

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