The British School of Bahrain Chemistry Department9F+Workbook… · · 2013-01-13The British...

The British School of Bahrain

Chemistry Department

Year 9 Workbook

9F Patterns of Reactivity

Name

Form

2

*P40126A0228*

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

9F Target Sheet

9

F

Name Class

Topic Targets Before the unit I have learned this I have revised this9Fa 1 Know the name of the gas in the air

that reacts with metals most easily.

2 Know that some metals are unreactive in air.

3 Know the name of the gas that is given off when metals react with water.

4 Know the names of the compoundsthat form when metals reactwith water.

9Fb 1 Know the name of the gas that is given off when metals react with acids.

2 Know the names of the salts formed from the three common laboratory acids.

3 Know how to place metals in order of reactivity based on their chemical properties.

4 Know how to write word equations for the reactions of metals with air, water and acids.

9Fc 1 Know about displacement reactions.

2 Know how to write word equations for displacement reactions of metals.

3 Know how to use the Reactivity Series to predict whether a displacement reaction will take place.

4 Know how to use the results of displacement reactions to place metals in order of reactivity.

9Fd 1 Know the names of metals used to make a variety of different objects.

2 Know some properties of these metals.

3 Know some factors that affect the reaction of a metal with acid.

4 Know how the extraction and discovery of metals links to their reactivity.


Page 1 of 2

9Fa/1 Hotting up 1

9

F

a

Name Class

In these experiments you will find out what affects the amount of heat given off.When calcium reacts with water the tube gets hot.

Experiment 1: Changing the amount of calcium

Method

1 Measure out 10 cm3 of water in the measuring cylinder.

2 Pour it into the boiling tube.

3 Measure the temperature of the water and write it in the table.

4 Ask your teacher for a piece of calcium. Your teacher will drop it into the water.

5 As soon as the reaction is finished, measure thetemperature of the liquid.

6 Wash out your tube.

7 Repeat the experiment with two pieces ofcalcium, and then three pieces.

P

Recording your results

Apparatus� Boiling tube � Thermometer � Tube rack� Measuring cylinder � Eye protection� Calcium granules (from your teacher)

�Do not touch the piecesof calcium. Your teacherwill handle the calcium

using forceps.Wear eye protection.

Pieces of calcium Water temperature Water temperature Temperature rise (oC)

at the start (oC) at the end (oC)

1

2

3

Considering your results/conclusionsThe more pieces of calcium we used .

The factors that were the same each time were .

It was a fair test because .

Page 2 of 2


9Fa/1 Hotting up 1 (continued)

9

F

a

observing, consideringS


Method

1 Measure out 5 cm3 of water in the measuringcylinder.

2 Pour it into the boiling tube.

3 Measure the temperature of the water and write it in the table.

4 Ask your teacher for a piece of calcium. Yourteacher will drop it into the water.

5 As soon as the reaction is finished, measure the temperature of the liquid.

6 Wash out your tube.

7 If you have done experiment 1, write the result for 10 cm3 of water into yourtable. If you have not done this experiment already, do it now.

8 Repeat the experiment with 15 cm3 of water.

?


using forceps.

Volume of water (cm3) Water temperature Water temperature Temperature rise (oC)

at the start (oC) at the end (oC)

5

10

15

Considering your results/conclusionsThe more water we used .

The factors that were the same each time were .

It was a fair test because .

Experiment 2: Changing the volume of water


9Fa/2 Hotting up 2

9

F

a

Page 1 of 2

In these experiments you will find out what affects the amount of heat given offwhen calcium reacts with water.

Preliminary experiment

Method

1 Measure 10 cm3 of water and pour it into the boiling tube.

2 Measure the temperature of the water.

3 Ask your teacher for a piece of calcium. Your teacher will drop it into the water.

4 When the reaction is finished, measure the temperature of the liquid.

P Apparatus� Boiling tube � Thermometer� Measuring cylinder � Eye protection� Calcium granules � Tube rack

(from your teacher)



Planning

Now plan an investigation which will look at how the temperature rise might beaffected by:

� the number of pieces of calcium that you use� the volume of water.

1 Write a plan. You will need to think about: � whether you will investigate one variable or both� how many experiments you need to carry out� the range of values that you will investigate (e.g. What is the maximum

volume of water? What will be the difference in water volume between one test and the next?)

� how you can check your results. (Is it possible to co-operate with other groups and swap data?)

Predictions

2 Predict how the temperature rise will be affected by:a the volume of waterb the amount of calcium.

3 Explain your reasoning. Is it possible to predict the actual temperature that mightbe reached in each case?

Page 2 of 2


9Fa/2 Hotting up 2 (continued)

9

F

a


4 Carry out your experiment and record your results in a neat table.

5 If you have enough results, draw a graph or graphs to display your results.

Considering your results/conclusions

6 What factors affect the temperature rise?

7 Are there any definite number patterns in the results?

8 Did this agree with your predictions?

9 Can you explain the findings using scientific reasons?

Evaluation

10 Which factors did you keep the same each time?

11 a In what ways was the test not completely fair?

b How might this be overcome?

12 a Did you have enough results?

b Did all the results fit the general trend?

13 Are you fully confident of your conclusions, or do you need to check your data, or try any extra experiments to confirm your ideas?

planning, observing, presenting, considering, evaluatingS


9Fa/3 Reactions withwater

9

F

a

aluminium

AlNo reaction with cold orhot water. Will react withsteam to producealuminium oxide andhydrogen.

magnesium

MgVery slow reaction withcold water. Slow reactionwith hot water. Reactsreadily with steam to formmagnesium oxide andhydrogen.

calcium

CaReacts rapidly with coldwater. Hydrogen gas isgiven off. The water turnsmilky white.

potassium

KViolent reaction. Potassiumfloats on the surface of thewater, melts and thencatches fire. Burns with alilac coloured flame.Hydrogen gas given off.

�

gold

AuNo reaction with cold orhot water. No reactionwith steam.

sodium

NaRapid reaction. Sodiumfloats on water, and movesaround rapidly. Heat fromthe reaction melts thesodium. Hydrogen gasgiven off.

iron

FeIron will rust slowly incold water.

zinc

ZnNo reaction with cold orhot water. Will reactslowly with steam toproduce zinc oxide andhydrogen.

copper

CuNo reaction with cold orhot water. No reactionwith steam.

silver

AgNo reaction with cold orhot water. No reactionwith steam.

knowledgeS


9Fa/4 Metals and water 1

9

F

a

Name Class

knowledgeS

1 Some metals react with water and others do not. Unscramble the letters toget the correct metal.

a I do sum floats on water and reacts very quickly to form an alkali

b Mega minus burns with a bright white flame and reacts very slowly

with cold water

c Orni goes rusty if you leave it in water

d Imacluc reacts quickly with water and makes the water go white

e Pc rope is used for piping because it does not react with water

2 Put the five metals in order, from the most reactive to the least reactive.

1 2 3

4 5

3 Emma did an experiment in which she looked at the reactions of metals inair. She got these results: sodium (most reactive), magnesium, calcium, iron,copper (least reactive). How do Emma’s results compare with your answer toquestion 2? Tick the correct box.

?

*If you ticked one of these boxes, say what the differences are here:

4 Complete the word equations for these reactions. Here is an example:

sodium + water → sodium hydroxide + hydrogen

a calcium + water → calcium hydroxide +

b + water → potassium hydroxide + hydrogen

c + → lithium hydroxide + hydrogen

The order is exactly the same.

The order of reactivity is roughly the same, but there are some differences.*

The order is totally different.*


9Fa/5 Metals and water 2

9

F

a

knowledgeS

1 Choose your answers from the words in the box. Each answer is used only once.

?

Give the name of:

a two metals which float on water and react very quickly to form alkalis

b a metal which burns with a bright white flame and reacts slowly with cold water

c a metal which goes rusty if you leave it in water

d a metal which reacts quickly with water and makes the water go white

e a metal which is still used for piping because it does not react with water

f a metal which used to be used for piping but is no longer used because ofthe risk of poisoning the water supply.

2 Look at the sketch of the Periodic Table.

Which section of the table includes:

a unreactive metals and non-metals

b the most reactive metals

c metals that are less reactive.

calcium copper iron lead magnesium potassium sodium

3 Two of the metals in the list below react with water, giving off a gas andproducing metal hydroxides. The other two metals do not react.

sodium lead copper calcium

a Which two metals do not react?

b Write word equations for the reactions of the other two metals with water.

4 Carlton wrote in his exercise book:

A

B

C

The metals that react best with oxygen are the same as the ones whichreact best with water. If you put them in order of reactivity, the order isexactly the same. All the metals which burn also react with water.

Do you agree with Carlton or not? Explain your answer.


9Fa/6 Looking for patterns

9

F

a

When metals react with oxygen they turn into metal oxides and they gain in mass.

Sanjay wondered whether the gain in mass might be linked to the reactivity of the metal.

Clare wondered whether there was any relationship between the gain in mass and theposition of the element in the Periodic Table.

They collected the data in the table and tested their ideas. All the figures in the tablerefer to the mass of metal oxide formed when 10 g of metal was heated andcompletely converted into the metal oxide.

presenting, considering, evaluatingS

Metal Mass of oxide Increase Percentage Atomic Order of

formed (g) in mass increase number reactivity

aluminium 18.9 5

calcium 14.0 3

copper 12.5 9

iron 14.3 7

lead 10.3 8

magnesium 16.7 4

potassium 14.2 1

sodium 13.5 2

zinc 12.5 6

1 Copy the table.

2 Work out the increase in mass for each metal.

3 Calculate this as a percentage (remember that you started with 10 g of each metal).

4 Plot a scatter graph showing the percentage increase in mass and the order of reactivity of the metals.

5 Look up the atomic number of each of the elements on the Periodic Table.

6 Plot a second scatter graph showing the percentage increase in mass againstatomic number.

7 Were Sanjay’s or Clare’s ideas right? For each graph decide whether:� there is a definite relationship between the variables, that applies to all

the metals� there is a relationship (a correlation) that applies to most of the metals –

and if so, which elements do not fit the trend� there is definitely no relationship between the variables.

8 How sure are you about the conclusions that you have drawn? Are there anyother different elements that you could get data for, which would help youto come to more definite conclusions?

9 What important factor has not been considered at all in this analysis thatmay help to explain any anomalous results?

?


Page 1 of 2

9Fb/1 Reactions of metalswith acids 1

9

F

b

Name Class

PredictionYou will be using calcium, copper, iron, magnesium and zinc.

Make a prediction of the order of reactivity of these metals with acid, starting with themost reactive one.

1 2 3

4 5

Method

1 Take a dry test tube to your teacher, who will give you a piece of calcium.

2 Fill a different test tube about 1/3 full with dilute hydrochloric acid.

3 Carefully tip the piece of calcium into the test tube containing the acid.

4 Add a piece of one of the metals.

5 If any gas is given off, test it with a lighted splint.

6 Feel the tube to see if it is warm.

7 Look to see if the metal has reacted in the acid.

8 Record your results in the table.

9 Repeat the test with other metals.

P Apparatus� Test tube rack � Five test tubes� Wooden splints � Eye protection� Dilute � Bunsen burner

hydrochloric acid � Heatproof mat� Samples of calcium, copper,

iron, magnesium and zinc



Page 2 of 2


9Fb/1 Reactions of metals with acids 1

(continued)

9

F

b



How many metals reacted? __________

How many did not react? ___________

What is the name of the gas that is given off ? ___________________________________

List the metals in order of reactivity, from the highest to the lowest.

1

2

3

4

5

How does this list compare with your predictions?

Metal Did you get Did the gas burn Did the metal react? Did the tube

bubbles? with a pop? get warm?

calcium

copper

iron

magnesium

zinc

Recording your resultsUse this table to record your results.


9Fb/3 Reactions of metalswith acids 3

9

F

b

aluminium

AlSteady reaction with acidsgiving off hydrogen gas,once the protective layerhas been ‘stripped off’ bythe acid.

magnesium

MgRapid reaction with acidsgiving off hydrogen gas.Heat from the reactionmeans that the tube willget warm.

calcium

CaVery rapid reaction withacids. Hydrogen gas isgiven off. Heat from thereaction means that theliquid in the tube gets hot.

potassium

KViolently explosivereaction with acids.Potassium reacts with theacid forming hydrogen gas.This reaction should notbe attempted in thelaboratory.

gold

AuNo reaction with anydilute acids. Only thestrongest mixtures ofconcentrated acids willattack gold.

sodium

NaVery violent reaction withacids. Possibly explosive.Sodium reacts with theacid forming hydrogen gas.This reaction should notbe attempted in thelaboratory.

iron

FeSlow reaction with diluteacids to produce hydrogen.

zinc

ZnSteady reaction with diluteacids to produce hydrogen.

copper

CuNo reaction with mostdilute acids. Copper willreact with concentratedacids.

silver

AgNo reaction with mostdilute acids. Silver willreact with someconcentrated acids.

knowledgeS

�

�


9Fb/4 Reactions withoxygen

9

F

b

knowledgeS

aluminium

AlNo reaction when in block form unless heated very strongly indeed. Burns readily in powder form.

magnesium

MgMagnesium ribbon burnsbrightly when heated in aflame. Magnesium powderburns very rapidly with awhite flash.

� �

calcium

CaCalcium pieces burnstrongly if heated in aflame for several minutes.

potassium

KMelts very easily and thencatches fire. Burns veryrapidly with a lilaccoloured flame.

� �

gold

AuNo reaction. Gold will meltif it is heated to a hightemperature, but it willnot burn. It does notoxidise in the air.

sodium

NaMelts easily and then setson fire. Burns rapidly witha yellow/orange flame.

�

iron

FeNo reaction in block form.Fine wire or filings willsparkle when put in aflame. Iron will rust slowlyin moist air.

zinc

ZnNo reaction when in block form. Burns inpowder form.

copper

CuMetal glows red whenheated in a strong flamebut does not burn. Thereis a black coating on themetal at the end.

silver

AgNo reaction in a flame.Silver will melt if it isheated to a hightemperature, but it willnot burn. Will react veryslowly with the air to formsilver oxide.


9Fb/5 Metals and acids 1

9

F

b

Name Class

knowledgeS

1 Draw lines to link the correct metal to each description

Which metal:

a reacts steadily with acids to give an orange-brown solution calcium

b reacts quickly with water and acids copper

c could explode if you reacted it with an acid iron

d does not react with water or acids magnesium

e reacts with acids and reacts very slowly with water sodium

2 When metals react with acids, which gas is given off? Circle the right answer.

hydrogen oxygen helium carbon dioxide

3 How do we test for this gas? Tick the correct box.

?

A B C D

A Relights aglowing splint

B Turns limewater milky

C Burns with asqueaky pop

D Puts out aburning splint

4 You have got some sulphuric acid that you need to store.

You could store it in:� a steel can� a glass jar� a plastic bottle.

a Which container is most likely to be corroded by the acid?

b Which container would be most likely to break if you dropped it?

c Which container would be the lightest and most flexible?

d How would you choose to store the acid?

e Why?



9

F

b

1 When metals react with acids, a gas may be given off.

a Name the gas.

b How do we test for this gas?


calcium + hydrochloric acid → calcium chloride + hydrogen

a calcium + nitric acid → calcium nitrate +

b + hydrochloric acid → zinc chloride + hydrogen

c magnesium + acid → magnesium chloride + hydrogen

d + sulphuric acid → iron sulphate +

3 Put these formulae next to the correct acid in the table.

H2SO4 HCl HNO3

knowledgeS

Acid Chemical formula

nitric

sulphuric

hydrochloric

?

4 You have got some sulphuric acid that you need to store.

You could store it in a metal can, a glass jar or a plastic bottle.

Give advantages and disadvantages for each type of container, and say whichone you think would be the best to choose.

Advantages of a metal can

Advantages of a glass jar

Advantages of a plastic bottle

Disadvantages of a metal can

Disadvantages of a glass jar

Disadvantages of a plastic bottle

Which would you choose?

Why?

Name Class



9

F

b

knowledgeS

1 The symbol equation for the reaction of zinc with sulphuric acid is:

Zn + H2SO4 → ZnSO4 + H2

a How many atoms are there in a molecule of hydrogen gas?

b Name one compound in this equation that does not contain a metal.

c What is the name of the compound with the formula ZnSO4?

d This is a balanced equation. Explain the meaning of ‘balanced’ in terms ofnumbers of atoms.

e Write a similar balanced symbol equation equation for the reaction ofmagnesium with sulphuric acid.

2 The formula of zinc chloride is ZnCl2. Here is an equation which shows theformulae of all the substances that take part in the reaction:

Zn + HCl → ZnCl2 + H2

a Write the formulae for:� the two reactants� the two products.

b The equation above is not fully correct. It is not balanced. Explain why it iswrong.

The balanced equation is written like this:

Zn + 2HCl → ZnCl2 + H2

c This diagram illustrates the equation.

?

In the diagram, which symbol represents:

i an atom of zinc

ii an atom of hydrogen

iii a molecule of hydrogen?

d Kevin wrote that the correct symbol equation should be

Zn + HCl → ZnCl + H

Kevin’s equation is balanced, but it is not correct. Explain why Kevin’sequation is not correct.


9Fb/8 Which metal reactsbest?

9

F

b

The table shows the results of an experiment in which 0.2 g of metal was reacted withhydrochloric acid. The volume of gas given off was measured every 10 seconds untilall of the metal had reacted.

considering, presentingS

1 Plot a line graph of the volume of gas against time. Use a different line foreach metal, and label the lines to show which metal is which.

2 When is the reaction of calcium the fastest – after 10, 20 or 30 seconds?Explain your answer by referring to the graph or table.

3 Explain why the reaction slows down as time goes on. You may find ithelpful to use the particle model to help with your explanation.

4 List the three metals in order of:

a how quickly they react at the start of the reaction

b the order in which they stopped reacting

c the amount of gas produced by each metal.

5 a Why is it difficult to say which metal reacts ‘best’?

b What would be a better word to use?

6 Explain as fully as you can why the magnesium line crosses over the calcium line.

7 What would you say is the best measure of reactivity – the speed of thereaction at the start or the amount of gas at the end? Explain your answer.

?

Volume of gas (cm3) released by each metal

Time (s) calcium magnesium zinc

0 0 0 0

10 60 45 20

20 90 80 30

30 105 110 39

40 113 135 47

50 117 155 54

60 119 172 60

70 120 186 65

80 120 194 69

90 120 199 72

100 120 200 74

110 120 200 75

120 120 200 75


9Fc/1 Displacement reactions 1

9

F

c

Considering your results/conclusions5 Add up the total number of reactions for each of the metals, and write it in the table.

6 Put the metals in order of reactivity.

7 Add up the total number of reactions for each of the compounds and write it inthe table.

8 Put the compounds in order of reactivity.

9 How does the list of metals compare with the list of compounds?

10 Here is a word equation for the reaction of zinc with copper sulphate:

zinc + copper sulphate → copper + zinc sulphate

Write word equations for the reactions that took place in your experiments.

In this experiment, you will investigate the reactions of metal elements withcompounds of other metals.

Planning

1 Collect a copy of the results sheet (9Fc/2).

2 Choose a colour, and underline the four elements.

3 Choose a different colour, and underline the four compounds.

4 Fill in the key by your table to show the colours of the elements and compounds.


Method1 Take three test tubes, and fill them about 1/3 full with copper sulphate solution.

2 Add a small piece of iron to one tube, lead to the second tube andmagnesium to the third tube.

3 Leave the tubes for several minutes. Check to see if there is any reaction.Look for:� colour changes on the surface of the metal� colour changes in the solution� bubbles of gas given off� a temperature rise.

4 Write your results in the table.

5 Repeat the experiment with the other solutions.

? Apparatus� Test tube rack � Test tubes� Eye protection � Thermometer� 3 pieces each of copper, iron, lead and magnesium� Solutions of copper sulphate, iron sulphate, lead

nitrate and magnesium sulphate

�Wear eye

protection.

copper iron lead magnesium total

sulphate sulphate nitrate sulphate reactions

copper X

iron X

lead X

magnesium X

total


9Fc/2 Displacement reactions results sheet

9

F

c

Name Class


Key elements compounds

Order of reactivity of metals: Order of reactivity of compounds:

1 1

2 2

3 3

4 4

Results sheet


9Fc/6 Reactivity wordsearch 1

9

F

c

Name Class

literacy, knowlegeS

There are 15 metals hidden in the wordsearch grid. The names all go across or down.

1 Sort the metals into three groups – high, medium and low reactivity. Some havebeen done for you.

2 Choose one colour for each group and show this on your chart.

3 Find the metals on the wordsearch grid.

4 Colour them in the correct colour.

Metals: aluminium calcium copper gold iron

lead lithium magnesium mercury platinum

potassium sodium silver tin zinc

High reactivity Medium reactivity Low reactivity

lithium tin mercury

platinum

Colour code: Colour code: Colour code:

S P A L U M I N I U M

T O V E R E V E R P O

U T S A B R I G O L D

C A P D Z C R S N A L

A S O D I U M I R T I

L S T I N R I L T I T

C I I A C Y O V E N H

I U U C O P P E R U I

U M X I N C M R A M U

M A G N E S I U M U M


9Fc/7 Reactivity wordsearch 2

9

F

c

Name Class

literacy, knowledgeS

Use the clues on this sheet to identify the names of 15 metals. Write the name in thespace after the clue and then find these metals on the wordsearch grid.

The number of letters in each word is given at the end of the clue. Some of the cluesinclude the names hidden or jumbled up – look for the metals in the words printed in italics.

1 Unreactive metal that is preferred by the police? (6)

2 Metal that bursts into flames when it reacts with water. (9)

3 Jewellery metal hidden in a packet of Persil? Very strange! (6)

4 Metal in the middle of the Reactivity Series – or in jumble? (4)

5 Metal that reacts with water, and is needed for healthy teeth and bones. (7)

6 The least reactive metal that you have studied in this Unit. (4)

7 Unreactive metal that is also a liquid. (7)

8 Make a metal element from the symbols for titanium and nitrogen. (3)

9 Metal that burns brightly in oxygen, but does not react with water. (9)

10 Metal that is below half way in the Reactivity Series – but if you read the namedifferently it sounds as though it’s out in front. (4)

11 Precious metal found mixed up in a plum tin. (8)

12 Reactive metal used in street lamps because it gives an orange glow. (6)

13 Metal that is quite high in the reactivity series – although it often seems much lower. (9)

14 Metal which reacts with acids. It sounds as though you might wash your dishes in it. (4)

15 The least reactive metal in Group 1 of the Periodic Table. (7)

S P A L U M I N I U M

T O V E R E V E R P O

U T S A B R I G O L D

C A P D Z C R S N A L

A S O D I U M I R T I

L S T I N R I L T I T

C I I A C Y O V E N H

I U U C O P P E R U I

U M X I N C M R A M U

M A G N E S I U M U M


9Fd/1 Investigating reactivity 1

9

F

d


Method

1 Measure out 10 cm3 of hydrochloric acid and pour it into the boiling tube.

2 Measure the temperature of the acid, and write it down.

3 Take the piece of magnesium. Drop it into the boiling tube and start timing.

4 Watch what happens to the magnesium and the acid.

5 When the reaction is finished, stop the clock. Note the time.

6 Measure the temperature of the liquid in the tube.

P Apparatus� Eye protection � Piece of magnesium (1 cm long)� Boiling tube � Test tube rack� Stopclock � Measuring cylinder (10 or 25 cm3) � Dilute hydrochloric acid� Thermometer

�Wear eye

protection.


1 What are the names of the two reactants in this experiment?

2 Which one is

a an element?

b a compound?

3 How could you tell that a reaction was taking place?

4 How long did the reaction take?

a Did the liquid get warmer or colder during this reaction?

b What was the temperature change?


9Fd/3 Reactive and unreactive metals 1

9

F

d

Name Class

knowledge, literacyS

1 Write the name of the correct metal in the space provided.

Choose your answers from the box.?

copper gold iron magnesium sodium

Which metal:

a is used in jewellery because it stays shiny?

b burns with a bright white flame?

c goes rusty?

d is used in coins and slowly goes black in air?

e reacts very quickly with the air before you put it in a flame?

2 a Which two metals in the list are the most reactive?

and

b Which two metals in the list are the least reactive?

and

3 Unscramble the names of these metals using the clues to help you.

a deal is a metal that is used for roofing because it does not react

with air and water

b nit is used for coating cans because it is less reactive than iron

c livers is a metal used for jewellery because it is unreactive

d atoms is up is a metal which is more reactive than sodium


aluminium + oxygen → aluminium oxide

a sodium + oxygen → oxide

b + oxygen → magnesium oxide

c copper + oxygen → copper

d calcium + → calcium oxide

e iron + oxygen →


9Fd/4 Reactive andunreactive metals 2

9

F

d

knowledgeS

1 Write the name of:

a an unreactive metal that is used in jewellery

b a metal that reacts very quickly with the air before you put it in a flame

c a metal which burns with a bright white flame

d a metal which reacts slowly with the air and goes rusty

e a metal which is used in coins and slowly goes black in air.

2 Arrange the five metals from question 1 in order, from the most reactive tothe least reactive.

3 a Unscramble the names of these metals using the clues to help you:

• nit is used for coating cans because it is less reactive than iron

• livers is a metal used for jewellery because it is unreactive

• atoms is up is a metal which is more reactive than sodium.

b There are three metals mentioned in question 3 a. Put them in order ofreactivity, starting with the most reactive.

4 Copy and complete these word equations by writing:

• the name of the product if a reaction takes place

• ‘no reaction’ if a reaction does not take place.

a sodium + oxygen →

b gold + oxygen →

c copper + oxygen →

d calcium + oxygen →

e iron + oxygen →

?


9Fd/5 Discovering andextracting metals

9

F

d

aluminium

Date of discovery: 1828

Extracted by: passing an electric currentthrough molten aluminium oxide(electrolysis)

magnesium


Extracted by: passing an electric currentthrough molten magnesium chloride(electrolysis)

calcium


Extracted by: passing an electric currentthrough molten calcium chloride(electrolysis)

potassium


Extracted by: passing an electric currentthrough molten potassium chloride(electrolysis)

gold

Date of discovery: known since ancient times

Found as the pure metal

sodium


Extracted by: passing an electric currentthrough molten sodium chloride(common salt)

iron


Extracted by: heating iron ore withcharcoal (smelting)

zinc

Date of discovery: before 1500

Extracted by: heating zinc ore withcharcoal (smelting)

copper


Extracted by: heating copper ore withcharcoal (smelting)

silver


Found as the pure metal

knowledgeS

Al

Ca

Cu

Au

Fe

Mg

K

Ag

Na

Zn


9Fd/6 Metal reactivity inaction 1

9

F

d

knowledgeS

Fact 1: Ships made of iron sometimes have blocksof magnesium attached to the hull.

Fact 2:Iron can be galvanised by coating it withzinc. This can protect the iron and stop itrusting.

Fact 3: Steel cans are sometimes coated with tin.Dented cans can be dangerous becauserust can get into the food.

Fact 4: Although aluminium is morecommon in the ground than iron,in Victorian times aluminium wasa very expensive metal.

Fact 5:Ancient gold jewellery is often in verygood condition when it is discovered.

Fact 6:The bronze age came before the iron age.

Shall I usethe aluminiumcutlery, m’lord?


9Fd/7 Metal reactivity inaction 2

9

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d

Look at each of the ‘Fact cards’ on worksheet 9Fd/6.

Each of the ‘Reason cards’ matches one of the ‘Fact cards’.

You could:

� write out each of the facts with the correct reason� cut out the cards and stick each ‘Fact card’ next to the correct ‘Reason card’.

knowledgeS

Reason AZinc is a more reactive metal than iron. The zinc will react first so that the iron is protected.

Reason BTin is less reactive than iron, so rust will not affect the metal can in normalconditions. When the can is dented, the iron can be exposed, and rust can get into the food.

Reason CGold is an unreactive metal. Even after thousands of years it doesn’t react with airor water.

Reason DAluminium is a reactive metal and it is very difficult to extract it from itscompounds without modern technology.

Reason EMagnesium is a reactive metal. The magnesium block reacts with the water beforethe iron. When the block has all reacted, it can be replaced before the hull of theship gets damaged.

Reason FBronze is mostly made of copper. Copper is an unreactive metal. It is possible tomake bronze by heating some types of rock in a fire. Iron ore has to be heated to amuch higher temperature to make iron.

✄


Page 1 of 2

9Fd/9 Explaining the reactivity of metals

9

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d

The Reactivity Series is a way of putting metals in order. It describes the way thatdifferent metals react. To explain why metals react in different ways, we have to godeeper inside the atom. Scientists used to believe that atoms were the smallestpossible particles. Just over 100 years ago, there were some experiments thatsuggested there were some particles that were even smaller. We now call theseparticles electrons. They carry the electrical current in a circuit, and are the cause ofall chemical reactions.

These days, we believe that the atom has a core (or nucleus) at the centre, withelectrons going round it. This model is a bit like the solar system with the planetsorbiting the Sun. The nucleus has a positive electrical charge, and the electronshave negative electrical charges. The positive and negative charges attract eachother. Each element has a different charge on the nucleus, linked to its position in the Periodic Table. The number of electrons in each atom can also be read off thePeriodic Table – for example hydrogen has one, oxygen has eight, and magnesiumtwelve.

The number of electrons and their distances from the nucleus can affect the reactivityof an element. The more electrons there are in an atom, the larger the atom is likelyto be, and this will have an influence on how easily the electrons on the outside ofthe atom can react. The more easily the electrons can react, the more reactive themetal will be.

Here is some data for Group 1 of the Periodic Table. In this group all the metals arereactive, and the reactivity increases as you go down the group. The atomic radius(radius of an atom) is measured in nanometres (one nanometre = 0.000 000 001 m).

electron

nucleus

H He

Li Be B C N O F Ne

Na Mg Al Si P S Cl Ar

Hydrogen Helium

lithium beryllium boron carbon nitrogen oxygen fluorine neon

sodium magnesium aluminium silicon phosphorus sulphur chlorine argon

1 2

3 4 5 6 7 8 9 10

11 12 13 14 15 16 17 18

Metal Number of electrons Atomic radius (nm) Order of reactivity

lithium 3 0.157 5

sodium 11 0.191 4

potassium 19 0.235 3

rubidium 37 0.250 2

caesium 55 0.272 1

Some elements from the Periodic Table.

An atom.

Page 2 of 2


9Fd/9 Explaining the reactivity of metals

(continued)

9

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d

knowledge, literacy, consideringS

1 a What name is given to the central part of the atom?

b What electrical charge does it have?

2 a What are the particles that move around the core of the atom called?

b What electrical charge do they have?

3 We know that atoms are electrically neutral overall. What does this tell usabout the charge on the core and the charge on the other particles in an atom?

4 Describe one way in which atoms are:

a similar to the solar system

b different from the solar system.

5 a What is the rule for the attraction of electrical charges?

b Will an electron feel a greater force of attraction when it is close to thenucleus, or when it is further away?

6 a Plot a graph of atomic radius (vertical axis) against number of electrons inthe atom (horizontal axis).

b Describe the relationship between the number of electrons and atomic radius.

c Describe the relationship between reactivity and atomic radius.

7 Two possible explanations for the reactions of metals are given below.

Explanation A: metals react when some of their outer electrons are given awayto other non-metal atoms.

Explanation B: metals react when they take in extra electrons from non-metal atoms.

Which of these explanations best fits the evidence? Explain why.

?


9F Word Sheets

9

F

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

Word Pronunciation Meaning

oxidised ocks-ee-dysed When a substance reacts with oxygen to form an oxide.

reactive A substance that reacts with many other substances, or reacts very easily.

unreactive A substance that reacts with few other substances, or reacts very slowly or not at all.

9Fa – Shine On/Stinging in the rain/Fire and water


corrode When something (such as stone or metal) reacts with chemicals in the air or water and gets worn away.

oxide ocks-eyed A compound formed when something reacts with oxygen.

Reactivity Series A list of metals which shows them in order of their reactivity, with the most reactive atthe top.

sulphates Compounds containing sulphur and oxygen. They are the type of salt formed when areaction with sulphuric acid occurs.

salt A compound made when acids react with metals or bases. Many salts are chlorides,sulphates or nitrates. Common salt is sodium chloride.

9Fb – Acid attack/League tables


electrolysis A process where electricity is used to split compounds apart, normally to produce an element.

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

9Fd – Heavy metal


bonds Forces holding particles together.

displace When one element takes the place of another in a compound – a type of substitution.

displacement reaction A reaction where one element takes the place of another in a compound.

9Fc – Knowing your place


Page 1 of 2

9F Summary Sheets

9

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Metals may react with substances around them in the environment such as air, water and acids.

Some metals react very easily or quickly. They are reactive. Other metals do not reactvery easily and are described as unreactive. The most reactive metals are found on theleft-hand side of the Periodic Table. Less reactive metals are found in the centre of thePeriodic Table.

Some gases are more reactive than others. In the air, oxygen is the most reactive gas.Nitrogen is not very reactive. When metals react with the oxygen in the air theyform oxides.

metal + oxygen metal oxide

The metals that react quickly with air also tend to react with water. When metalsreact with water they form hydrogen gas and a metal hydroxide.

metal + water metal hydroxide + hydrogen

The metals that react with water also react very quickly with acids. Some metals thatdon’t react with water do react with acids. When metals react with acids, they producehydrogen and a salt.

metal + acid salt + hydrogen

The name of the salt formed depends on the name of the acid:

� sulphuric acid makes sulphates� nitric acid makes nitrates� hydrochloric acid makes chlorides.

Reactivity SeriesMetals can be arranged in a Reactivity Series. The most reactive metals are placed atthe top of the table.

More reactive metals can displace less reactive metals from their compounds. In adisplacement reaction, the more reactive metal will form a compound, and the lessreactive metal is left on its own as the pure element.

For example, iron is more reactive than copper, so it will displace copper from acompound.

iron + copper chloride iron chloride + copper

Zinc is more reactive than iron, so iron will not displace zinc from a compound.

iron + zinc chloride no reaction

You can use displacement reactions to work out the position of a metal in theReactivity Series. For instance, zinc will displace lead from a compound, so we knowthat zinc is more reactive than lead.

The Reactivity Series can also be used to predict whether reactions will occur.

Patterns of reactivity

Page 2 of 2


9F Summary Sheets (continued)

The reactivity of metals can be linked to their uses. Metals used for construction needto have a low reactivity, otherwise they will corrode away. Some metals, such asaluminium, have a natural protective oxide layer. Others, such as iron, have to beprotected from corrosion, e.g. by painting.

Many low reactivity metals have been known for hundreds or thousands of years.They can be extracted by heating their compounds in a fire.

More reactive metals are extracted by electrolysis. This means that they have only been discovered in the last two hundred years, since the invention of the electric battery.

9

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Page 1 of 2

9Fa

1 The gas in the air that reacts with metalsmost easily is:

A argon. B carbon dioxide.

C nitrogen. D oxygen.

2 A metal that does not react with the air is:

A calcium. B gold.

C iron. D magnesium.

3 The gas which is given off when metalsreact with water is:

A carbon dioxide. B hydrogen.

C oxygen. D nitrogen.

4 Sodium reacts with water to form:

A sodium chloride.

B sodium oxide.

C sodium hydroxide.

D sodium carbonate.

9Fb

1 The gas which is given off when metalsreact with acids is:

A carbon dioxide. B hydrogen.

C oxygen. D nitrogen.

2 When magnesium reacts with sulphuricacid, it forms:

A magnesium oxide.

B magnesium chloride.

C magnesium sulphate.

D magnesium carbonate.

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

9

F

9F Quick Quiz

3 Look at these diagrams, and then choosethe correct order of reactivity for metals X,Y and Z (the most reactive metal shouldbe first).

A Z, X, Y B Y, Z, X

C X, Y, Z D Z, Y, X

4 Choose the correct statement to completethis word equation:

zinc + sulphuric acid →A zinc + sulphur + acid

B zinc hydrate + sulphur

C zinc sulphate + hydrogen

D zinc hydroxide + hydrogen

9Fc

1 Iron is more reactive than copper. If apiece of iron is put into copper sulphatesolution, what would you see?

A Brown copper would appear on the iron.

B Blue copper would appear on the iron.

C Nothing would happen.

D The iron would dissolve completely.

X ZY

Page 2 of 2


9F Quick Quiz (continued)

9

F

2 Zinc is more reactive than tin. It willdisplace tin from a compound. Choose thecorrect statement to complete this wordequation:

zinc + tin sulphate →A zinc + tin sulphate

B zinc + zinc sulphate

C tin + zinc sulphate

D tin + zinc chloride

3 Copper is more reactive than silver. Iron ismore reactive than copper. This means that:

A copper will react with iron nitratesolution.

B silver will react with iron nitratesolution.

C iron will react with silver nitratesolution.

D silver will react with copper nitratesolution.

4 Zinc reacts with copper sulphate solutionand silver nitrate solution. This meansthat zinc:

A is more reactive than copper and silver.

B is less reactive than copper and silver.

C is less reactive than copper but morereactive than silver.

D is less reactive than silver but morereactive than copper.

9Fd

1 Which of these materials is used to makemost car bodies?

A plastic

B aluminium

C copper

D steel

2 Some window frames are made ofaluminium. It is a good metal to usebecause:

A it conducts electricity.

B it conducts heat.

C it does not melt easily.

D it does not react very quickly with airor water.

3 Magnesium would react more slowly withacid if you:

A added more acid.

B added more water.

C heated the acid.

D used a more concentrated acid.

4 Which of these statements is true?

A Many reactive metals have been knownsince ancient times.

B Magnesium was discovered before iron.

C Reactive metals can be extracted byheating their compounds with charcoal.

D Most reactive metals were discoveredafter the invention of the electricbattery.

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