activity resources (teacher's edition) - 2 years

8/14/2019 Activity Resources (Teacher's Edition) - 2 Years

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SPN 21SPN 21CHEMISTRY

ACTIVITY RESOURCES

CHEMISTRY

ACTIVITY RESOURCES

Teachers Edition

OH SING SENG

GOH SIAH CHING

N RAZIMI HJ MUDA

ROSLENA HJ MUNEL

SRI YANI HEPNIE


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Page

INTRODUCTION TO CHEMISTRY 3

KINETIC PARTICLE THEORY 4 8

CHEMICAL FORMULA 9

TYPES OF COMMON CHEMICAL REACTIONS 10 25

STOICHIOMETRY AND MOLE CONCEPT 26 29

EXPERIMENTAL CHEMISTRY 30 33

ACIDS, BASES AND NEUTRALIZATION 34 38

SALTS 39 46

QUALITATIVE ANALYSIS 47 55

METAL AND EXTRACTION 56 64

THE PERIODIC TABLE 65 66

ENERGY FROM CHEMICALS 67 70

ELECTROLYSIS 71 76

SPEED OF REACTIONS 77 83

REVERSIBLE REACTIONS 84 86

REDOX 87 88

ATMOSPHERE AND ENVIRONMENT 89

ORGANIC CHEMISTRY 90 99

REFERENCES 100

CCoonntteennttss


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Activity 1.4

INTRODUCTION TO CHEMISTRY

Aim: Use mnemonics to familiarize with name and symbol of first row of common transition

metals.

Example:Use mnemonics to memorise the first row of the common transition metals.Scandium, Titanium, Vanadium, Chromium, Manganese, Iron, Cobalt, Nickel, Copper, and Zinc

ScaryTimVeryCrookedManICallNickCorporalZee

- Scandium- Titanium- Vanadium- Chromium- Manganese- Iron- Cobalt- Nickel- Copper- Zinc


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Activity 2.2

KINETIC PARTICLE THEORY

Aim: Using role play to demonstrate the movement of particles in solid, liquid and gas.

Procedure:1. A group of students (6- 9), stand at the front of the room acting as atoms.

2. Standing next to each other in 2 or 3 rows with arms linked they represent a solid- particles

closed together, moving slightly (vibrating) at their fixed position.

3. As heat energy is applied the students move further away from each other and eventually the

links break.

4. Allowing students to move randomly passing each other but still remain close together.

5. Further heating the students move freely away from each other at high speed.


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Activity 2.3


Aim: To determine the melting point of naphthalene using cooling curve.

Apparatus:ThermometerRetort standBoiling tube

Conical flaskBunsen burnerStopwatch

Materials:Solid naphthalene

Procedure:1. Clamp boiling tube on retort stand.

2. Add 3 spatulas of powdered naphthalene into a boiling tube and insert a thermometer.

3. Heat the naphthalene until all has melted (about 85 C ).

4. Then, leave it to cool in a conical flask.

5. Record the temperature for every 20 seconds until it falls to about 60 C .

6. Record the results in a table.


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Results:Cooling of naphthalene

Time (s) Temperature ( C ) Time (s) Temperature ( C )

0 16020 180

40 200

60 220

80 240

100 260

120 280

140 300

Analysis of data:

1. Plot a graph of temperature against time for the cooling of naphthalene.

2. From the graph deduce the melting point of naphthalene.

3. The melting point of naphthalene is C


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Activity 2.4


Aim: To determine the purity of ethanol by determining its boiling point.

Apparatus:Thermometer

Beaker 250 3cmRetort standBoiling tubeStirrer or glass rod

Tripod standWire gauzeBunsen burnerStopwatchPorcelain chip

Materials:WaterEthanol sample (Caution: ethanol is flammable)

Procedure:1. Quarter fill the boiling tube with your ethanol sample.

2. Add a porcelain chip to the boiling tube to ensure it does not froth up too much on boiling.

3. Set up apparatus as shown below.


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4. Heat the water gently and stir continuously to ensure an even temperature around the boiling

tube.

5. Continue heating until the ethanol boil. This is when the bubbles start to appear from the

porcelain chip.

Results:

1. Record the highest reading on the thermometer. .. C

2. Allow the ethanol to boil for one minute to see if the temperature change. Record this

temperature. C

Questions:1. The boiling point of ethanol is 78 C . Is your ethanol sample pure?

2. What effect does an impurity have on the boiling point of a substance?

3. Why must we heat the ethanol in a water bath and not heat it directly with a Bunsen flame?


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Activity 5.1

CHEMICAL FORMULA

Aim: To work out the formula of ionic compound using card games.

Materials:A set of cards representing common anions and cations. Each card has the symbol of the ionwritten on it.

Procedure:1. Group the students (2 to 3 students in a group).

2. Give each group a set of cards.

3. To get a correct formula, join the shapes to form a rectangle.

4. The formula can then be read or copied from the card.

For example, to find the formula of copper(II) chloride, a complete rectangle is formed by joiningone copper(II) ion card and two chloride ion cards (see below). Hence the formula of copper(II)

chloride is 2CuCl .

Questions:Now use the card to work out the chemical formulae of the following ionic compounds

(a) Potassium chloride(b) Zinc chloride(c) Copper(II) oxide(d) Potassium sulphate

(e) Potassium manganate(VII)(f) Sodium hydrogencarbonate(g) Potassium dichromate(VI)(h) Magnesium hydroxide(i) Sodium hydroxide

(j) Iron(II) sulphide(k) Sodium sulphate(l) Iron(III) hydroxide(m) Ammonium nitrate

(n) Iron(II) nitrate(o) Iron(II) sulphate(p) Iron(III) sulphate(q) Ammonium sulphate


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Activity 6.2

TYPES OF COMMON CHEMICAL REACTIONS

Aim: To show relative reactivity of metals with water.

Apparatus:Test tubes with rackPair of forcepsKnife or scalpel

White tileWater trough (for sodium only)

Materials:Sodium (store in oil) teachers demonstrationCalciumMagnesiumIron

CopperDistilled water

Procedure:1. Place distilled water in four test tubes to a depth of 5 cm.

2. Drop a piece of calcium into a test tube filled with water.

3. Observe the reaction carefully and answer the following questions:

(a) Does the metal float or sink in water?

(b) Does the metal react vigorously?

4. Test the gas given out using lighted splint

5. Dip a piece of red litmus to the solution in the test tube. Is there a colour change?

6. Repeat step 1, 2, 3, and 4 for the other metals.

7. Record all your observations in a table provided under the Results section.


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Results:

ObservationsElement

Float or SinkVigorous or

Not vigorous

Lighted splint testEffect on redlitmus paper

Magnesium

Copper

Calcium

Sodium

Iron

From the results arranged the five metals in the order of decreasing reactivity.

Most reactive Least reactive

............................., .............................., ............................., ..............................., ..............................

Questions:

1. Which group of the Periodic Table does sodium belong?.....

2. What is the common name for this group of metals?

.

3. Name the alkali formed when sodium reacts with water.

.

4. Name the gas produced when sodium reacts with water.

.....................................

5. Which other metals (listed above) will produce similar reaction with cold water?

.

6. Name this type of reaction.

.

7. Write a balanced equation for the above reaction.

.


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Activity 6.3


Aim: To show reaction between metals with dilute hydrochloric acid (Reactivity Series of Metals)

Apparatus:Test tubes with rack

Chemicals:Zinc foilMagnesium ribbonCopper foil

Iron wireDilute hydrochloric acid solution

Procedure:1. Place dilute hydrochloric acid in a test tube to a depth of 2 cm.

2. Drop a piece of zinc into the test tube.

3. Test the gas given out using a lighted splint.

4. Repeat step 1, 2 and 3 for magnesium, copper and iron.

5. Record all your observations in a table provided in the Results section.


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Results:

Metals Observations Lighted splint test

Copper

Zinc

Magnesium

Iron

From the results arranged the four metals in the order of decreasing reactivity.


....................................., ......................................, ....................................., .......................................

Questions:1. Write the chemical formula for hydrochloric acid.

.

2. Name the gas given out when dilute acid reacts with a metal..................................................................................................................................................

3. Name the metals (listed above) other than zinc that produces similar reaction with acid.

.

4. What would you expect the reaction to be if potassium is used instead of zinc in the above

reaction?

.

5. Although copper is a metal, it does not react with dilute hydrochloric acid. Why?

.

6. Name the salt formed when zinc reacts with dilute hydrochloric acid.

.

7. Name this type of reaction

.


.


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Activity 6.4


Aim: To show reaction of carbonates with dilute hydrochloric acid.

Apparatus:Test tube with rackBoiling tube

Delivery tube (or plastic syringe)Spatula

Chemicals:Calcium carbonate powderCopper(II) carbonate powderDilute hydrochloric acid solutionLimewater

Procedure:1. The test tube is filled with dilute hydrochloric acid to a depth of 3 cm.

2. One spatula of powdered calcium carbonate is added to the dilute hydrochloric acid.

3. Pass the gas given out into limewater.

4. Repeat step 1 and 3 for powdered copper(II) carbonate.

5. Record all your observations in the table provided.

Dilute hydrochloric acid

Boiling tube

Calcium carbonate powder


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Results:

Observations Limewater test

Calcium carbonate

Copper(II) carbonate

Questions:Calcium carbonate

1. Name the gas given out in the reaction..

2. Is calcium carbonate soluble in water?

.

3. Name the salt formed when calcium carbonate reacts with dilute hydrochloric acid?

.

4. Is this salt soluble in water?

.

5. Name this type of reaction.

.


.

Copper(II) carbonate1. What is the colour of copper(II) carbonate?

........

2. Is copper(II) carbonate soluble in water?

.

3. Name the gas given out in the above reaction.

.

4. Write a balanced chemical reaction for the above reaction.

.


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Activity 6.5


Aim: To show precipitation reaction.

Apparatus:Test tubes

Materials:Potassium iodide solutionLead(II) nitrate solutionSilver nitrate solution

Sodium sulphate solutionBarium chloride solutionDilute hydrochloric acid solution

Procedure:1. Pour potassium iodide solution into a test tube (about 2 cm depth) and add an equal volume of

lead(II) nitrate solution and observe.

2. Leave the mixture to stand for a few minutes and observe.

3. Repeat step 1 and 2 for:

(a) silver nitrate and dilute hydrochloric acid solutions

(b) Sodium sulphate and barium chloride solutions

Results:

Reaction Initial observations When left to stand

(a) Potassium iodide +Lead(II) nitrate solution

(b) Silver nitrate + Dilutehydrochloric acid

(c) Sodium sulphate + bariumchloride


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Questions:1. Name the precipitate formed in experiment (a), (b) and (c).

Experiment (a): ..

Experiment (b): ..

Experiment (c): ..

2. Write the balanced chemical equations for experiment (a), (b) and (c).

Experiment (a): ...

Experiment (b): ...

Experiment (c):


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Activity 6.6


Aim: To show displacement reaction between metals.

Apparatus:

Beaker 50 3cmMeasuring cylinder

Sand paper

Materials:Magnesium ribbonLead(II) nitrate solutionZinc foilCopper(II) sulphate solution

Silver nitrate solutionMagnesium chloride solutionCopper foil

Procedure:1. Clean a strip of magnesium ribbon with a sand paper.

2. Pour about 20 3cm of lead(II) nitrate solution into a beaker.

3. Immerse the magnesium ribbon in the lead(II) nitrate solution.

4. Leave the mixture aside for few minutes, and observe.

5. Repeat the above experiment using the following:

(i) Zinc foil and copper(II) sulphate solution,

(ii) Magnesium ribbon and silver nitrate solution,(iii) Copper foil and magnesium chloride solution.


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Results:

Reaction Observations Conclusion

Magnesium+

lead(II) nitrate solution

Zinc+

copper(II) sulphate solution

Magnesium+

silver nitrate solution

Copper+

Magnesium chloride solution


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Activity 6.7


Aim: To show displacement reaction between halogens.

Apparatus:Test tubes

Materials:Chlorine waterBromine waterSodium bromide solution

Potassium iodide solutionIodineSodium chloride solution

Procedure:1. Pour potassium iodide solution into a test tube (about 2 cm depth).

2. Add an equal volume of chlorine water and observe.

3. Record your observations in the table provided.

4. Repeat the experiment for the following reaction:

(i) Chlorine water and sodium bromide solution,

(ii) Bromine water and sodium chloride solution,

(iii) Bromine water and potassium iodide solution,

(iv) Iodine and sodium chloride solution,

(v) Iodine and sodium bromide solution.


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Results:

HalidesHalogen

NaCl (aq) NaBr (aq) KI (aq)

Chlorine

Bromine

Iodine

Questions:1. From the results, arrange the three halogens in the order of decreasing reactivity.


., ., ..

2. Write the balanced chemical equation for the following reactions:

(a) Chlorine and sodium bromide

..

(b) Chlorine and potassium iodide

..

(c) Bromine and potassium iodide

..


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Activity 6.8


Aim: To show thermal decomposition of carbonates.

Apparatus:Pyrex glass test tubeTest tube with rackTest tube holder

Delivery tube (or plastic syringe)Bunsen burner

Materials:Copper(II) carbonate powder

Ammonium carbonate powderLimewaterZinc carbonate powder

Procedure:

1. Put some powdered copper(II) carbonate into a Pyrex test tube and heat it strongly.

2. Pass the gas given out through limewater and observe.

3. Record your observations in the table provided.

4. Repeat the experiment with ammonium carbonate and zinc carbonate.


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Results:

Reaction Observations Limewater test

(a) Copper(II) carbonate

(b) Zinc carbonate

(c) Ammonium carbonate

Questions:1. What is the colour of the residue in experiment (a)?

2. What is the colour of the residue in experiment (b)?

3. Do you see any residue in experiment (c)? Why?

4. Write the balanced chemical equation for all the reactions.

(i) Experiment (a): ..

(ii) Experiment (b): ..

(iii) Experiment (c): ..


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Activity 6.9


Aim: To show direct reactions by heating

Part 1: Heating iron with sulphur

Apparatus:CruciblePipeclay triangleTripod stand

TongSpatulaBunsen burner

Materials:Iron filingsSulphur powder

Procedure:1. Mix one spatula full sulphur powder with an equal amount of iron filing in a crucible.

2. Heat the mixture strongly and observe.

Results:

Observation: ...

Questions:1. Name the product of the reaction.

2. Write the equation for the reaction.


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Part 2: Heating sulphur with air (oxygen)

Apparatus:CruciblePipeclay triangle

Tripod stand

TongSpatula

Bunsen burner

Materials:Sulphur powderBlue litmus paper

Strip filter paperAcidified potassium dichromate(VI)

Procedure:1. Add one spatula full sulphur powder into a crucible.

2. Then, heat strongly and observe.

3. Test the gas given out using moist blue litmus paper and acidified potassium dichromate(VI)

paper.

4. Record your observations in the table

Results:

Test Observations

Using moist blue litmuspaper

Using acidified potassiumdichromate(VI) paper

Questions:1. Name the product of the reaction.

2. Write the equation for the reaction.


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Activity 7.1

STOICHIOMETRY AND MOLE CONCEPT

Aim: To prepare standard solution of copper(II) sulphate.

Part 1:

Preparation of 0.1 3dmmol copper(II) sulphate solution

Apparatus:

Volumetric flask 250 3cmBeakerBalance

Glass rod

Materials:

Distilled waterCopper(II) sulphate crystals

Procedure:1 Use the balance to weigh _______ g of copper(II) sulphate pentahydrate crystals.

2 Dissolve the copper(II) sulphate in distilled water inside a beaker.

3 Pour the solution into a 250 3cm volumetric flask.

4 Add distilled water until the graduation mark on the neck of the graduated flask.

Results:

The solution prepared is 0.1 3dmmol copper(II) sulphate solution.

The solution contains . mole OH5.CuSO 24 in 13dm solution.


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Part 2:

Preparation of 0.01 3dmmol copper(II) sulphate solution from 0.1 3dmmol copper(II) sulphate

solution.

Procedure:

1 Pipette 25 3cm of copper(II) sulphate solution from Part 1.

2 Pour the solution into a 250 3cm volumetric flask.

3 Add distilled water until the graduated mark on the neck of the graduated flask.

Results:

The solution prepared is 0.01 3dmmol copper(II) sulphate solution.

The solution contains mole OH5.CuSO 24 in 13dm solution.

Questions:

ionconcentratFinalionconcentratOriginalxfactorDilution

1. Calculate the dilution factor from the above equation?

X


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Activity 7.2

STOICHIOMETRY AND MOLE CONCEPT

Aim: To determine the percentage purity of sodium carbonate in a mixture of sodium carbonate

and ammonium carbonate.

Apparatus:Bunsen burner with matchesTripod standCrucible

Pipeclay triangleTongsSpatula

Materials:Sample of impure sodium carbonate (sodium carbonate mixed with ammonium carbonate)

Procedure:

1. Weigh the mass of the crucible.

2. Then add in sample of impure sodium carbonate and weigh.

3. Place the crucible on the tripod stand, and heat it strongly for five minutes.

4. Leave the crucible to cool and weigh the content again.


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Results:(a) Mass of the empty crucible = .. g

(b) Mass of the crucible + impure sample of sodium carbonate = .. g

(c) Mass of impure sample of sodium carbonate [(b) (a)] = .. g

(d) Mass of crucible after heating = .. g

(e) Mass of pure sodium carbonate [(d) (a)] = .. g

Formula to calculate percentage purity:

Questions:

Calculate the percentage purity of sodium carbonate.

%100mplemass of sa

lece in samptanre subsmass of pu=puritypercentage


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Activity 8.1

EXPERIMENTAL CHEMISTRY

Aim: To obtain copper(II) sulphate crystals from a mixture of copper(II) sulphate and sand.

Apparatus:

250 3cm beaker

250 3cm conical flaskFilter paperFilter funnel

Stirring rodEvaporating dishBunsen burnerTripod stand

Materials:A mixture of copper(II) sulphate with sand

Procedure:1. Put the mixture in a beaker

2. Add water to the mixture

3. Stir with a glass rod to make sure that copper(II) sulphate dissolved.

4. Filter the mixture; collect the filtrate in a conical flask.

5. Wash the residue on the filter paper with water.

6. Evaporate the filtrate until saturated, and leave it to crystallize.


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Results:1. The residue is

The filtrate is ...

The solvent is

2. Explain why the residue is washed with water.

3. Give an example of a mixture of two other substances that can be separated by this method.


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Activity 8.5

EXPERIMENTAL CHEMISTRY

Aim: To separate various dyes in food colouring and measure the R values.

Apparatus:Boiling tubeFilter paperRuler

Pair of scissorsDistilled water

Materials:Mixture of food colouring

Procedure:1. Cut a strip of filter paper such that it can fit neatly into a boiling tube. It should also be slightly

longer than the boiling tube.

2. Draw a baseline with a pencil, about 2 cm away from the bottom tip.

3. Mark a tiny spot on the middle of the baseline with food colouring.

4. Put about 1cm depth of distilled water into the boiling tube.

5. Mount the filter paper strip in the boiling tube.

6. Leave the apparatus to stand for a short while.

7. Observe the solvent front as the water travels up the paper.

8. Remove the piece of filter paper when the solvent front reaches just below (1cm) the top of the

paper. [DO NOT let the solvent front go beyond the top of the paper]

9. Allow the paper to dry.

spotbaseline


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Results:Attach your chromatogram in the space below.

Questions:

1. What is the principle behind paper chromatography?

2. Calculate theR for each colour.


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Activity 9.1

ACIDS, BASES AND NEUTRALIZATION

Aim: To neutralise hydrochloric acid by titrating with sodium hydroxide solution.

Apparatus:

Materials:Solution P is dilute hydrochloric acid of unknown concentration

Solution Q is 0.1 3dmmol sodium hydroxide solution

Methyl orange or screened methyl orange indicator.

Procedure:1. Fill the burette with solution P until 0 mark. Make sure that no air bubbles are trapped at the tip

of the burette.

2. Pipette a 25.0 3cm portion ofQ into a conical flask. Add a few drops of either screened methyl

orange or methyl orange indicator.

3. Titrate the solution Q with the solution P from the burette and record the results in the table,

repeating the titration as many times as you consider necessary to achieve consistent results.


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Results:

Titration number 1 2 3

Final burette reading / 3cm

Initial burette reading / 3cm

Volume ofP used / 3cm

Best titration results ()

Summary:Tick () the best titration results.

Using these results, the average volume ofP required was . 3cm .

Volume ofQ used was . 3cm

Hence,

. 3cm of NaOH required ................ cm3 of HCl

Questions:1. Calculate the number of moles of sodium hydroxide used in the titration.

2. Write a balanced equation for the neutralisation of HCl by NaOH.

3. How many moles of HCl would be used in neutralising NaOH in the titration?

4. Having known the number of moles of hydrochloric acid from (3) and also the volume of the

acid used in the titration, calculate the concentration in 3dmmol of the hydrochloric acid.


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Activity 9.2


Aim: To titrate sodium carbonate and hydrochloric acid and to find percentage purity of sodium

carbonate.

Materials:

Solution P is 0.2 3dmmol hydrochloric acid

Solution Q is made by dissolving 28 g of a mixture of sodium chloride and sodium carbonate in

water and made up to 1 3dm solution.

Procedure:You are required to find the percentage purity of sodium carbonate in the mixture.

1. Put solution P in a burette.2. Pipette a 25.0 3cm portion ofQ into a conical flask. Add a few drops of either screened methyl

orange or methyl orange indicator.

3. Titrate the solution Q with the solution P from the burette and record the results in the table,

repeating the titration as many times as you consider necessary to achieve consistent results.

Results:

Titration number 1 2 3Final burette reading / 3cm

Initial burette reading / 3cm

Volume ofP used / 3cm

Best titration results ()

Summary:In the above titration cm3 of solution P is required to exactly neutralise

... cm3

of solution Q.


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Questions:1. Write a chemical equation to show the reaction involved in the titration.

2. From the titration, calculate the concentration of sodium carbonate in solution Q in 3dmmol .

3. Given that the molecular mass of sodium carbonate, 32CONa is 106, calculate the

concentration of sodium carbonate in solution Q in 3dmg .

4. Calculate the percentage purity by mass of sodium carbonate in the original mixture used in

the preparation of solution Q.


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Activity 9.3


Aim: To show reaction between sodium hydroxide and ammonium chloride

Apparatus:Test tube with rackTest tube holder

Bunsen burnerSpatula

Materials:Sodium hydroxide solutionSolid ammonium chlorideLitmus paper

Procedure:

1. Put one spatula full solid ammonium chloride into a test tube and slowly pour in sodium

hydroxide solution. Smell the gas.

2. Warm the mixture gently by using a small Bunsen flame.

3. Test the gas by using moist red and blue litmus paper.

Results:

1. When aqueous sodium hydroxide is added to solid ammonium chloride and warmed gently a

gas is formed. Describe the smell of the gas.

2. Test the gas with moist blue litmus paper. Describe your observation.

3. Test the gas with moist red litmus paper. Describe your observation.

Conclusion:

1. When an ammonium salt reacts with an alkali gas is formed, which turnmoist .. litmus paper . .

2. Write an equation for the reaction between sodium hydroxide and ammonium chloride.


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Activity 10.1

SALTS

Aim: To prepare copper(II) sulphate crystals by reacting sulphuric acid with

copper(II) oxide or copper(II) carbonate

Apparatus:BeakerConical flaskStirrerFilter funnel

Filter paperEvaporating basinSpatula

Materials:Dilute sulphuric acidCopper(II) oxide or copper(II) carbonate

Procedure:1. Put about 100 cm3 of dilute sulphuric acid in a beaker and heat it gently.

2. Add copper(II) oxide or copper(II) carbonate to the hot sulphuric acid, a little at a time until in

excess.

3. Filter out the excess copper(II) oxide or copper(II) carbonate by using filter funnel and filter

paper.

4. Collect the filtrate in an evaporating basin and evaporate the filtrate until saturated.

5. Leave the saturated filtrate to cool and crystallise.


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Questions:1. Name the base or carbonate used in this reaction?

2. What is the formula of this compound?

3. Is this compound soluble or insoluble?

4. Name the above reaction.

5. Write chemical equation for the above reaction.

6. Name the salt formed from the above reaction.

7. Name the filtrate.

8. What is the residue left on the filter paper?

9. Why must the copper(II) oxide be added in excess?

10. Can the above reaction be carried out using titration method? Why?


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Activity 10.2

SALTS

Aim: To prepare insoluble salts


Materials:Silver nitrate solutionPotassium iodide solution

Dilute hydrochloric acid solutionDilute nitric acid solution

Procedure:Carry out the following tests and record your observations in the table.

Testno.

Test observations

1 (a) To a portion of silver nitrate solution,add dilute hydrochloric acid until achange is seen.

(b) Leave the mixture to stand for a fewminutes and observe.

2 (a) To a portion of potassium iodidesolution, add lead(II) nitrate solutionuntil a change is seen.

(b) Leave the mixture to stand for a fewminutes and observe.


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Questions:1. Name the above reaction.

2. Write the symbol and ionic equations for the reactions between silver nitrate and hydrochloric

acid.

(a) Symbol equation

..

(b) Ionic equation

..

3. Write the symbol and ionic equations for the reactions between potassium iodide and lead(II)nitrate.

(a) Symbol equation

..

(b) Ionic equation

..


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Activity 10.3

SALTS

Aim: To investigate solubility of salts in water

Apparatus:Test tubes with rackStoppersSpatula

Materials:Distilled WaterSolid salts:Silver chlorideSodium chloride

Lead(II) chlorideBarium sulphateCopper(II) sulphate

Lead(II) sulphateSodium carbonate

Calcium carbonatePotassium nitrateSilver nitrate

Procedure:1. Add half a spatula of a salt to a test tube.

2. Half-fill the test tube with distilled water. Then stopper the tube and shake well.

3. Record your observation in the table provided.

Results:

SaltSolubility

(soluble or insoluble)

Silver chloride

Sodium chloride

Lead(II) chloride

Barium sulphate

Copper(II) sulphateLead(II) sulphate

Sodium carbonate

Calcium carbonate

Potassium nitrate

Silver nitrate


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Questions:

State whether you think the following substances are soluble or insoluble in water:

(a) Zinc nitrate

(b) Potassium nitrate

(c) Copper(II) carbonate

(d) Sodium nitrate

(e) Ammonium chloride


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Activity 10.4

SALTS

Aim: To determine the solubility of salts in 3cmg .

Apparatus:BeakersGlass rodSpatulaBalance

Filter funnelFilter paperMeasuring cylinder

Materials:

Water

Solid salts: sodium chloride and copper(II) sulphate

Procedure:

1. Label each beaker with the name of the salts. Measure 100 3cm water into each beaker.

2. Record the mass of these beakers containing water.

3. Add a spatula of sodium chloride salt and stir till dissolved.

4. Repeat step 3 until no more salt can dissolve in the 100 3cm of water.

5. Filter this salt solution and collect the filtrate.

6. Record the mass of this salt solution (filtrate).7. Subtract this new mass with the previous mass.

8. The difference will represent the solubility of the salt in 3cm100g .

9. This solubility can then be converted to 3dmg .

10. Repeat the experiment with copper(II) sulphate salt.

11. Record your results in the table.


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Results:

Sodium chloride salt Copper(II) sulphate salt

Mass of beaker + 100 3cm water / g (a)

Mass of salt solution (filtrate) / g (b)

Solubility in 3cm100g (a) (b)

Solubility in 3dmg

Conclusion:


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Activity 11.1

QUALITATIVE ANALYSIS

Aim: To identify the following cations: 3 Al ,

4NH , 2Ca , 2Cu , 2Fe , 3Fe and 2Zn

Apparatus:Test tubes with rackTest tube holderBunsen burner

Materials:Aqueous sodium hydroxide solutionAqueous ammonia solution

Aqueous solution of the following salts:Aluminium sulphate AAmmonium chloride BCalcium chloride CCopper(II) sulphate D

Iron(II) sulphate EIron(III) chloride FZinc nitrate G

Procedure:A, B, C, D, E, F and G are unknown solutions containing different cations. Carry out the followingtest and record your observations in the table. You should test and name, where possible, anygases evolved.

Testno.

Test Observations

(a) To a portion ofA add aqueous sodiumhydroxide until a change is seen.

(b) Add an excess of aqueous sodiumhydroxide to the mixture from (a).

1

(c) To a portion ofA add aqueousammonia until a change is seen.

(d) Add an excess of aqueous ammonia tothe mixture from (c).


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Testno.

Test Observations

2 (a) To a portion ofB add equal volume ofaqueous sodium hydroxide.

(b) Then warm gently

(c) To a portion ofB add equal volume ofaqueous ammonia.

3 (a) To a portion ofC add aqueous sodium

hydroxide until a change is seen.


(c) To a portion ofC add equal volume ofaqueous ammonia.

(a) To a portion ofD add aqueous sodiumhydroxide until a change is seen.


4

(c) To a portion ofD add aqueousammonia until a change is seen.



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Testno.

Test Observations

(a) To a portion ofE add aqueous sodiumhydroxide until a change is seen.


5

(c) To a portion ofE add aqueousammonia until a change is seen.

(d) Add an excess of aqueous ammonia to

the mixture from (c).

(a) To a portion ofF add aqueous sodiumhydroxide until a change is seen.


6

(c) To a portion ofF add aqueousammonia until a change is seen.


(a) To a portion ofG add aqueous sodiumhydroxide until a change is seen.


7

(c) To a portion ofG add aqueousammonia until a change is seen.



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Questions:

Give the names and formulae of the cations present in:

Name Formula

Solution ASolution B

Solution C

Solution D

Solution E

Solution F

Solution G


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Activity 11.2


Aim: To identify the following anions: 2

3CO , Cl , I ,

3NO and 2

4SO

Apparatus:Test tubes with rackTest tube holderBunsen burner

Materials:Aqueous solution of the anions above:Sodium carbonate ASodium chloride B

Potassium iodide CSilver nitrate DSodium sulphate - E

Aqueous barium chlorideAqueous lead(II) nitrate

Aqueous sodium hydroxideAluminum foilDilute nitric acid

Students are required to carry out tests to identify the anions in solutions A, B, C, D and E.

State eitherpositive ( ) ornegative ( X ) for each test using the reagents belowSolution

Dilute nitric acid 3 AgNO (aq) 2BaCl (aq) 23 )NO(Pb (aq)NaOH + Al

and heat

A

B

C

D

E


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Anion

present

Observations

P

rocedure

Reagen

tgiving

positiv

etest

Writethepositivetestfo

rtheanions

A,

B,

C,

D

andE

inthespacesprovided

Solution

A B C DE


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Activity 11.3


Aim: To test for gases

Apparatus:Bunsen burnerLitmus paperSpatulaFilter paper

Test tube holderPlastic syringeTest tubes with rackWooden splint

Materials: Acidified potassium dichromate (VI) Dilute hydrochloric acidDistilled water

Ammonium chloride solution

Hydrogen peroxide solutionBleach solutionLimewater

Solid calcium hydroxideManganese(IV) oxide

Sodium sulphiteCalcium carbonateMagnesium ribbon

Procedure:1. Generate the gas as described in the table.

2. Note its colour and odour and record your observations in the table

3. Carry out specific tests described in column 3 and record your observations.

Note: Use a test tube holder when heating anything in a test tube.


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TestNo.

Gas observations Specific Test and observations

1 HydrogenPut one magnesium ribbon

into a test tube.

Then add 2 3 3cm ofdilute hydrochloric acid intothe test tube.

Wooden splint testInsert a lighted wooden splint into the

mouth of the test tube.

2 Oxygen

Put 2 3 3cm of hydrogenperoxide into a test tube.

Then add a small amountof manganese(IV) oxideinto the test tube.

Wooden splint testInsert a glowing wooden splint into themouth of the test tube.

3 Carbon dioxidePut calcium carbonate intoa test tube.

Then add 2 3 3cm of

dilute hydrochloric acid intothe test tube.

Limewater testCollect the gas using plastic syringe thenpass the gas into test tube containinglimewater then shake.

4 Sulphur dioxidePut sodium sulphite into atest tube.

Then add 2 3 3cm ofdilute hydrochloric acid intothe test tube and heat.

Litmus testHold moist blue litmus paper in the gas.

Potassium dichromate(VI) testHold a piece of filter paper dipped inacidified potassium dichromate(VI) in the

gas.

Potassium manganate(VII) testHold a piece of filter paper dipped inacidified potassium manganate(VII) in thegas.


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TestNo.

Gas observations Specific Test and observations

5 Chlorine

Add about 2 3cm of dilute

hydrochloric acid into a testtube.

Then add about 2 3cm ofbleach solution.


6 AmmoniaPut ammonium chloridesolution into a test tube.

Then add one spatula ofsolid calcium hydroxide andwarm gently.

Litmus testHold moist red litmus paper in the gas.

7 Water vapourOne third fill a boiling tubewith water

Then heat gently.

Hold a piece of blue cobalt chloride paperin the gas.

8 Nitrogen dioxide(N 2006, P 3)

Put one spatula of sodiumnitrite in a test tube.

Then add about 2 3cm ofdilute hydrochloric acid.



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Activity 12.1

METALS AND EXTRACTION

Aim: To compare the reactivity of metals by displacement reaction.

Apparatus:Test tubes with rackSandpaperSpatula

Materials:Magnesium ribbonZinc foilsIron fillingsCopper foils

1 3dmmol Magnesium sulphate solution

1 3dmmol Zinc sulphate solution

1 3dmmol Iron (II) sulphate solution

1 3dmmol Copper (II) sulphate solution

Procedure:1. Clean a strip of magnesium ribbon with sandpaper.

2. Half fill a test tube with zinc sulphate solution.

3. Immerse the magnesium ribbon in the zinc sulphate solution.

4. Leave the mixture aside for a few minutes, and observe.

5. Repeat the experiment above using the materials stated in the table.


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Results:

Observations with

Magnesium Zinc Iron Copper

Magnesiumsulphate solution

Zinc sulphatesolution

Iron(II) sulphatesolution

Copper(II) sulphatesolution

Questions:

1. From your results arrange the four metals in order of decreasing reactivity.


................................... , ................................... , ................................... , ................................... .

2. Complete these displacement equations:

CuSO4 (aq) + Fe (s) __________ + _________

FeSO4 (aq) + Zn (s) __________ + _________

ZnSO4 (aq) + Mg (s) __________ + _________

3. Aluminium is more reactive than zinc but less reactive than magnesium. Will aluminiumdisplace iron from a solution of iron (II) salt? Explain.


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Activity 12.2


Aim: To show Thermit reaction (reduction of metal oxide) demonstration only.

Apparatus:Sand bathPaper cone made from filter paperSpatula

Materials:Iron(III) oxide

Aluminium powderMagnesium powder

Magnesium ribbonBarium peroxide (or potassium chlorate)

Procedure:1. Mix a few grams of iron(III) oxide powder with an equal amount of aluminium powder and put

the mixture in a paper cone mounted on a sand bath as shown in the diagram.

2. Mix a little barium peroxide or potassium chlorate with magnesium powder and pour the

mixture into the paper cone containing the mixture of iron(II) oxide and aluminium powder. This

mixture is to set off a preliminary reaction.

3. Using a long piece of clean magnesium ribbon as a fuse, stick one end into the base of the

paper cone and burn the other end.

[Caution: Immediately move far away from the burning magnesium ribbon.]

Sand bath

Paper cone

Mixture of

iron(III) oxide andaluminium powder

Mixture of barium peroxide and

magnesium powder

Magnesium ribbon

as fuse


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Results:

1. Describe the reaction.

2. Write the equation to show the reaction between iron(III) oxide and aluminium.

...


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Activity 12.3


Aim: To show the action of heat on the carbonates.

Apparatus:Test tubes with rackTest tube holders

Bunsen burnerPlastic syringe (or delivery tube)

Materials:Zinc carbonateCopper(II) carbonateLime water

Procedure:

1. Put some powdered zinc carbonate into a test-tube and heat it strongly.

2. Pass the gas given out through lime water and observe for the formation of a new substance.

3. Repeat the experiment using copper(II) carbonate and observe for the colour change and the

formation of a new substance.

Results:(a) Zinc carbonate is (colour). When strongly heated zinc carbonate gives out a

(colour) gas which turns lime water

(b) The residue is (colour) when hot and (colour) when cold.

(c) The gas is and the residue is

(d) Write word equation for the above reaction.

(e) Write symbol equation for the above reaction.

(f) Copper(II) carbonate is (colour). When strongly heated copper(II) carbonate

gives out a (colour) gas which turns lime water

(g) The residue is (colour)

(h) The gas is and the residue is

(i) Write word equation for the above reaction.

(j) Write symbol equation for the above reaction.


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Activity 12.4


Aim: To determine the conditions for rusting

Apparatus:Boiling tubesTest tube rack

Materials:Iron nailsBoiled water

Cooking oilTap water

Procedure:1. Prepare four boiling tubes in a rack, labelled them as A, B, C and D.

2. Into each boiling tube place a clean iron nail.

3. Pour water from the tap into boiling tube A until the nail is fully submerged.

4. Pour some hot water into boiling tube B until the nail is fully submerged and pour a layer of

cooking oil to cover the surface of the water.

5. Place a little anhydrous cobalt chloride into boiling tube C and cork the mouth of the boiling

tube with a rubber bung.

6. Pour some cooking oil into boiling tube D until the nail is fully submerged.

7. Leave the four boiling tubes in the rack for a few days and then observe.

Results:(a) Does the tap water in boiling tube A contain air? Why?

(b) Does the water in boiling tube B contain air? Why?

(c) Does the air in the boiling tube C contain water? Why?

(d) Does boiling tube D contain any air or water?

(e) Which iron nail becomes rusty?

(f) Why does the iron nail become rusty?


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Activity 12.5


Aim: To show sacrificial protection of metal.Apparatus:3 Petri dishesCotton wool

Materials:Salt solutionIron nailsMagnesium ribbonCopper foil

Procedure:1. Fill the three Petri dishes with some salt solution and then make a cushion of cotton wool and

place it in each Petri dish so that it is soaked in the salt solution.

2. Label the Petri dishes as A, B, and C.

3. In Petri dish A, place a clean iron nail on the cushion of cotton wool. In Petri dish B, place a

clean iron nail wound with magnesium ribbon and in Petri dish C, place a clean iron nail wound

with copper strip.

4. Leave the three Petri dishes for a few days and then observe.

Copper foil

cotton wool soakedin salt solution

Magnesium ribbon

A B C


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Results:1. What happen to the iron nail in A?

...

2. Which iron nail shows no rusting? Why?

3. What is the difference between iron nail in A from that in C?

4. Explain your observation in 3.


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Activity 12.6


Aim: To reduce lead(II) oxide by carbon.

Apparatus:Bunsen burnerBlow pipe

Materials:Lead(II) oxideCarbon block

Procedure:

1. Wet the middle of carbon block using tap water.2. Place a little amount of lead(II) oxide on a carbon block.3. Heat and blow air using blow pipe over the oxide.4. Observe any changes on the carbon block.

Observations:

...

...

lead(II) oxidecarbon block

blow pipe

Bunsen burner


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Activity 13.1

THE PERIODIC TABLE

Aim: To show reactivity of Group I metals with water.Apparatus:BeakerScalpel

Pair of forcepsWhite tile

Materials:LithiumPotassiumSodium

Litmus paperPhenolphthalein

Procedure:

1. Put a few drops of phenolphthalein in a 250 3cm beaker containing water.

2. Cut a very small piece of lithium and drop it in water, and observe.

3. Repeat the above experiment with the following metals: sodium and potassium.

4. Record your observations in the table.

Results:

Metal ObservationsEffect of solution on

red litmus paper

Effect onphenolphthalein

indicator

Lithium

Sodium

Potassium

Lumps of lithiumor sodium orpotassium

White tile

Lithium or sodiumor potassium


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Questions:

1. Place the three metals in the order of decreasing reactivity.


, ,

From the results, it shows that when a metal reacts with water, the solution formed is

. The compound formed is an .

The gas given off in the reaction is

2. Write a balanced chemical equation for the reaction between lithium and water.

3. Write a balanced chemical equation for the reaction between sodium and water.

4. Write a balanced chemical equation for the reaction between potassium and water.


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Activity 14.1

ENERGY FROM CHEMICALS

Aim: To find H using 0.1 3dmmol HCl and 0.1 3dmmol NaOH solutions.

Apparatus:

Two 100 3cm measuring cylinders

250 3cm beakers

ThermometerPlastic cup

Materials:

0.1 3dmmol HCl solution Q

0.1 3dmmol NaOH solution P

Procedure:In this question you are required to determine the heat of neutralisation between a strong acid HY

and a strong alkali MOH.

You are provided with the following.

(a) Solution P is 0.1 3dmmol alkali MOH.

(b) Solution Q is 0.1 3dmmol acid HY.

1. Using a measuring cylinder measure 100 cm3 ofQ into a plastic cup and then measure the

temperature.

2. Using another measuring cylinder measure 100 cm3 ofP into a 250 cm3 beaker and similarly

measure the temperature.

3. Record the temperature of the two solutions and calculate the mean temperature.

4. Slowly pour the solution Q into the beaker containing solution P.

5. Stir the mixture with the thermometer and record the maximum temperature reached.


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Results:

Initial temperature of the acid Q = ...... )a(

Initial temperature of the alkali P = .. )b(

Mean initial temperature [ 2)ba( ] = .. )c(

Maximum final temperature of mixture = .. )d(

Temperature increase [d c] = .. )e(

(Assume that the density of HCl and NaOH is 1 3cmg )

Questions:1. Write an equation to show the neutralisation between P and Q.

2. Write an ionic equation for the above reaction.

3. Ignoring the heat lost to the plastic container and the beaker, calculate the heat given out by

the reaction. (The specific heat of solution is 4.2 gJ C).

[Hint: Use the formula H = m x c x ]

4. Calculate the number of mole of the acid HY or the alkali MOH involved in the reaction.

5. Calculate the heat of neutralisation, H, between MOH and HY.


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Activity 14.2


Aim: To investigate heat of solution of salts.

Apparatus:Plastic cupThermometerSpatula

Materials:Sodium hydroxide

Ammonium chloride

Procedure:

1. Measure out 50 cm3 of water in a measuring cylinder and pour it into a plastic cup.

2. Measure the initial temperature of the water.

3. Add a spatula full of solid sodium hydroxide into the water in the cup.

4. Stir to dissolve the solid.

5. Record the highest temperature obtained.

6. Repeat step 1- 4 with ammonium chloride and for step 5 record the lowest temperature

obtained.

[Repeat with other salts; nitrates, sulphates, carbonates etc.]

Result:

ReactionInitial

temperature/ CFinal

temperature/ CChange in

temperature/ C

Exothermicor

Endothermic

Sodium hydroxide +water

Ammonium chloride +water

Conclusion:


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Activity 14.3


Aim: To set up Daniel cell.

Apparatus:BeakerVoltmeter

Materials:Copper plateZinc plate

1.0 3dmmol zinc sulphate solution

1.0 3dmmol copper(II) sulphate solution

VoltmeterConnecting wires

Procedure:1. Set up copper metal as the positive terminal and zinc metal as the negative terminal.

2. Immerse the zinc metal in zinc sulphate solution and the copper metal in copper(II) sulphate

solution.

3. Connect the two solutions using a salt bridge as shown.

Or connect the two solutions using a porous pot as shown below.

Results:

The electrode potential of Daniel cell is . V

salt bridge

zinc platecopper plate

zinc sulphatesolution

copper(II) sulphatesolution

copper platezinc plate

zinc sulphatesolution

copper(II) sulphatesolution

porous pot copper can

copper(II)sulphate solution

zinc sulpha esolution

porous pot

voltmeter

zinc


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Activity 15.1

ELECTROLYSIS

Aim: To demonstrate electrolysis of molten lead(II) bromide.

Apparatus:CrucibleSpatulaGraphite electrodesPower pack

Crocodile clipsTripod standClay pipe triangleBunsen burner

Materials:

Lead(II) bromide

Procedure:1. A crucible is half filled with lead(II) bromide solid.

2. The solid lead(II) bromide is heated until it melts to a molten state.

3. Two carbon electrodes are dipped in the molten lead(II) bromide and are then connected to

power pack using crocodile clips.

4. Electric current is allowed to flow through for 15 minutes and the changes that occur at the

cathode and anode are recorded.

Results:

Observations Inference

At the anode

At the cathode


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Activity 15.2

ELECTROLYSIS

Aim: To demonstrate electrolysis of dilute sodium chloride solution.

Apparatus:Power packCarbon electrodesCrocodile clips

100 3cm beaker

Materials:

Aqueous 0.5 3dmmol sodium chloride solution

Procedure:

1. Aqueous sodium chloride is put into a beaker2. Insert two carbon electrodes into the aqueous sodium chloride and connect them to the power

pack.

3. The switch is turned on and electric current is allowed to flow for 15 minutes and observe.

4. Collect the gas and test.


Results:

Electrolyte Observations Test for the gas

At the cathode: Splint test

Dilute sodiumchloride solution At the anode: Splint test

aqueous sodium chloridecarbon electrodes


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Activity 15.3

ELECTROLYSIS

Title: To Demonstrate electrolysis of concentrated sodium chloride solution.


100 3cm beaker

Materials:

Concentrated sodium chloride solution (1 3dmmol )

Procedure:

1. Concentrated sodium chloride is put into a beaker.

2. Insert two carbon electrodes into the concentrated sodium chloride solution and connect them

to the power pack.


4. Collect the gas and test.


Results:

Electrolyte Observations Test for the gas

At the cathode: Splint test

concentrated sodiumchloride solution At the anode: Litmus test

concentrated sodiumchloride solution

carbon electrodes


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Activity 15.4

ELECTROLYSIS

Aim: To demonstrate electrolysis of copper(II) sulphate using carbon electrodes.


100 3cm beaker

Materials:

Aqueous 0.5 3dmmol copper(II) sulphate solution

Procedure:

1. Copper(II) sulphate solution is put into a beaker.2. Insert two carbon electrodes into the copper(II) sulphate solution and connect them to the

power pack.



Results:

Electrolyte Observations

At the cathode:

Copper(II) sulphatesolution At the anode:

Questions:1. What would you expect the colour of the copper(II) sulphate solution to be if the electrolysis is

carried out for a long period? Why?

2. Describe a test for the product formed at the anode.


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Activity 15.5

ELECTROLYSIS

Aim: To demonstrate electrolysis of copper(II) sulphate using copper electrodes.

Apparatus:Power packCopper electrodesCrocodile clips

100 3cm beaker

Materials:

Aqueous 1.0 3dmmol copper(II) sulphate solution

Procedure:1. Copper(II) sulphate solution is put into a beaker.

2. Insert copper electrodes into the copper(II) sulphate solution and connect them to the power

pack.



Results:

Electrode Observations

At the cathode:

Copper(II) sulphatesolution At the anode:

Questions:1. What would you expect the colour of the copper(II) sulphate solution to be if the electrolysis is

carried out for a long period? Why?


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Activity 15.6

ELECTROLYSIS

Aim: To demonstrate electroplating of spatula with copper.

Apparatus:Power pack

Beaker 250 3cmCrocodile clips

1.0 3dmmol copper(II) sulphate

Copper plateMetal spatula

Materials:

1.0 3dmmol copper(II) sulphate

Procedure:

1. Pour about 200 3cm of 1.0 3dmmol copper(II) sulphate solution into a beaker.

2. A piece of copper plate is connected to the positive terminal. This plate act as the anode.

3. The metal spatula is connected to the negative terminal. This metal spatula acts as the

cathode.

4. Immerse both the metal spatula and the copper plate in the copper(II) sulphate solution. (Make

sure that they do not come into contact)

5. The solution is electrolysed for 30 minutes using a small current (0.5A ).

Results:

Observations Half-equations

At the cathode: At the cathode:

At the anode: At the anode:


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Activity 16.1

SPEED OF REACTIONS

Aim: To show the effect of concentration on the speed of reaction.

Apparatus:BeakerStop-watch

Filter paper marked XMeasuring cylinders

Materials:

2.0 3dmmol hydrochloric acid

0.25 3dmmol sodium thiosulphate, 322 OSNa solution

Distilled water

Procedure

1. Measure 5 3cm of sodium thiosulphate solution into a 250 3cm beaker and add 45 3cm of

distilled water.

2. Place the beaker over the filter paper marked X.

3. By using a separate measuring cylinder, add 10 3cm of 2.0 3dmmol HCl and at once start the

stop-watch.

4. Swirl the beaker a few times and then put the beaker back on the paper over the mark X.

5. Observe the mark X from above through the solution mixture in the beaker.

6. As more precipitate is formed the mark X will eventually disappears from sight.

7. Stop the stop-watch when the mark X just disappears from sight. Record the time taken in the

table below.

8. Repeat the experiment by changing the volume of sodium thiosulphate and distilled water.

9. Record the time taken in the table provided.


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Results:

Volume of sodiumthiosulphate solution,

3cm

Volume of distilledwater

3cm

Volume ofhydrochloric acid

3cm

Reaction times

5

10

15

20

25

Draw the graph of volume of sodium thiosulphate in 3cm against time in seconds.

Conclusion:As the concentration of sodium thiosulphate increases ..

...

...

...


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Activity 16.2

SPEED OF REACTIONS

Aim: To show the effect of temperature on the speed of reaction.

Apparatus:BeakerStop-watchFilter paper marked X

Measuring cylinderThermometer

Materials:

2.0 3dmmol hydrochloric acid

Distilled water

0.25 3dmmol sodium thiosulphate, 322 OSNa solution

Procedure:

1. Measure 20 3cm of sodium thiosulphate solution into a beaker and add 60 3cm of distilled

water. Record the temperature of the solution mixture.

2. Place the beaker over the filter paper marked X.

3. Add 20 3cm of 2.0 3dmmol HCl and at once start the stop-watch.

4. Swirl the beaker a few times and put the beaker back on the filter paper over the mark X.

5. Observe the mark X through the solution mixture.

6. Stop the stop-watch when the mark X just disappears from sight. Record the time taken in the

table provided.

7. Repeat the experiment at different temperatures by heating the mixtures of 20 3cm of sodium

thiosulphate and 60 3cm of distilled water to 40C, 50C, 60C and 70C.


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Results:

Temperature Reaction time in seconds Rate ( t1 )

Room temperature

40C

50C

60C

70C

Draw the graph of rate against temperature.

Conclusion:As the temperature increases ..

...

...

...


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Activity 16.3

SPEED OF REACTIONS

Aim: To show the effect of particle size using calcium carbonate (lump and powder) with

hydrochloric acid.

Apparatus:Conical flask connected to gas syringeStop-clockElectronic balance

Measuring cylinder 50 3cm

Materials:

Hydrochloric acid 0.25 3dmmol

Calcium carbonate (powder and lump forms)

Procedure:1. Use an electronic balance to weigh exactly 0.5 g of marble chips and put them in a conical

flask connected to a gas syringe.

2. Use a measuring cylinder to measure exactly 30.0 3cm of 0.25 3dmmol hydrochloric acid and

pour into the conical flask containing the marble chips.

3. Immediately cork the conical flask to the gas syringe and at the same time start the stop-clock.

4. Read the volume of the carbon dioxide collected in the gas syringe for every 10 seconds until

the reaction stops.

5. Create your own table to tabulate the readings.

6. Repeat the above experiment by using marble chips of (a) smaller size and (b) powdered

calcium carbonate.

7. Draw on the same graph paper the volume of carbon dioxide gas against time for the three

experiments.

Result:

Conclusion:As the particle size increases ..

...


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Activity 16.4

SPEED OF REACTIONS

Aim: To show the decomposition of hydrogen peroxide using manganese(IV) oxide.

Apparatus:

50 3cm measuring cylinderClockSpatulaConical flaskGas syringe

Delivery tubeRubber bungRubber tubing connectorRetort stand and clamp

Materials:

0.2 3dmmol or 2 volume hydrogen peroxide (20 volume diluted 10 x)

Powdered manganese(IV) oxide

Procedure:1. Set up the apparatus shown in the diagram.

2. Measure 50 3cm of hydrogen peroxide solution in the conical flask.

3. Add a little amount of manganese (IV) oxide into the hydrogen peroxide solution.

4. Immediately cork rubber bung to the conical flask and start timing.

5. Gently swirl the flask while recording the volume of gas collected in the gas syringe every

minute. Do this for 10 minutes or until the gas syringe is full. Take care not to undo the rubber

tube connector.

6. Record your results in table provided.

hydrogen peroxidesolution

manganese(IV) oxide


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Results:

Time/min 0 1 2 3 4 5 6 7 8 9 10

Volumeof gas/cm3

Plot a graph of volume of gas evolved (vertical axis) against time.

Conclusion:


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Activity 17.1

REVERSIBLE REACTIONS

Aim: To show reversible reactions.


Materials:Potassium chromate(VI) solution

Aqueous sodium hydroxideAqueous copper (II) sulphateConcentrated hydrochloric acidConcentrated ammonium hydroxideDilute sulphuric acid

Procedure:1. (a) Pour potassium chromate(VI) solution in a test-tube until it is about one-fifth full and

slowly adds dilute sulphuric acid until a change is seen.

Observation:

Write ionic equation for the reaction in (a).

(b) To the mixture from (a) slowly add dilute sodium hydroxide solution and observe the

change.

Observation:

..

..

Explain in terms of reversibility the observation in the experiment (b).


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2. (a) Pour copper (II) sulphate solution into a test-tube until it is about one-fifth full and slowly

add concentrated hydrochloric acid until a change is seen.

Observation:

..

..

Write the ionic equation for the reaction in (a).

..

(b) To the mixture from (a) add concentrated ammonia solution a little at a time until a change

is seen.

Observation:

3. State Le Chateliers principle.

......

......................................................................................................................................................


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Activity 17.2

REVERSIBLE REACTIONS

Aim: To prepare fertilizer using nitric acid (The manufacture of fertilizer from ammonia).

Apparatus:BurettePipettePipette filler2 conical flasksRetort stand

Evaporating dishBunsen burnerTripod stand and wire gauzeWhite tile

Materials:Dilute nitric acid

Aqueous ammonium hydroxide

Methyl orange indicator

Procedure:1. Place nitric acid in burette.

2. Pipette 25.0 cm3 of aqueous ammonium hydroxide into a conical flask. Add a few drops of the

indicator.

3. Titrate the acid with the alkali until neutralise.

4. Repeat titration, this time without the indicator.

5. Heat the mixture (ammonium nitrate solution) until it is saturated.

6. Transfer some mixture into an evaporating dish and leave to crystallise.

Conclusion:


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Activity 18.1

REDOX

Aim: To show the colour change in oxidizing agents - acidified potassium manganate(VII) and

acidified potassium dichromate(VI) solution.

Apparatus:Measuring cylinderBeakerConical flask

Test-tubeBurette

Material:Potassium manganate(VII) solutionPotassium dichromate(VI) solution

Dilute sulphuric acidSodium sulphite solution

Procedure:

1. Measure 20 3cm of potassium manganate(VII) solution into a conical flask and add about 5

3cm of dilute sulphuric acid.

2. From the burette, slowly add sodium sulphite solution (Na2SO3) into the conical flask until the

purple colour of potassium manganate(VII) disappears.

3. Repeat the experiment above using potassium dichromate(VI) solution.

Observations:

(a) Potassium manganate (VII) solution is (colour) due to the presence of

ions.

(b) As sodium sulphite solution is added, the colour changes to (colour) due to

the formation of ion.

(c) Potassium dichromate(VI) solution is (colour) due to the presence of

ions.

(d) As sodium sulphite solution is added the colour changes to (colour) due tothe formation of ion.

Conclusion:Potassium manganate(VII) and potassium dichromate(VI) are oxidizing agents. They are

by the reducing agent, sodium sulphite.


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Activity 18.2

REDOX

Aim: To show the colour change of iodide ion in redox reaction.

Apparatus:Boiling tubeTest tube

Materials:Hydrogen peroxide 20-volume,

1.0 3dmmol potassium iodide solution

Starch solution

Procedure:1. Pour about 5 3cm of potassium iodide solution into a boiling tube and slowly add equal volume

of 20-volume hydrogen peroxide, and observe.

2. Leave the mixture for a few minutes and observe for the formation of any solid substance.

3. Transfer some solution from the boiling tube into a test tube and add a few drops of starch

solution.

Results:(a) Potassium iodide solution changed from . (colour) to

. (colour) when added with hydrogen peroxide.

(b) When left to stand for a few minutes a . (colour) solid substance was

seen at the bottom of the boiling tube.

(c) When starch was added, the solution turned . (colour) showing that

. was formed.

Questions:1. Write an ionic equation to show oxidation of iodide ion.

2. Write an ionic equation for the reduction of hydrogen peroxide.

3. Write ionic equation to show redox reaction between potassium iodide and hydrogen peroxide.


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Activity 19.2

ATMOSPHERE AND ENVIRONMENT

Aim: To demonstrate water treatment using alum (Potassium aluminium sulphate).

Apparatus:

500 3cm beakersSpatula

Materials:Sample of muddy water

Alum

Procedure:1. Fill two beakers with muddy water until three quarter full.

2. Add a spoonful of alum in one but not the other.

3. Leave the two beakers for about 10 minutes and compare the appearance of the water in the

two beakers.

Observations:

...

...

muddy water

alum


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Activity 20.1

ORGANIC CHEMISTRY

Aim: To show incomplete combustion of hydrocarbon.

Apparatus:Bunsen burnerWooden splint

Evaporating dish

Materials:BenzeneTolueneKerosene

Procedure:

1. Place a little of each hydrocarbon into an evaporating dish.

2. Burn the hydrocarbon with a lighted wooden splint and observe for the products. (Note:

Burning should be carried out outside the lab as its burning will produce dense smoke and

carbon monoxide).

3. Observe the colour of the flame and record it in the table below

Results:

Hydrocarbon Formula Mr % of carbon Colour of the flame

Benzene 66HC

Toluene 356 CHHC

Kerosene 3215HC

Lightedwooden splint

Evaporating dish

Benzene


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Questions:1. Do you think these hydrocarbons make good fuel? Explain.

2. Which of the three hydrocarbons produces the least smoke? Relate your observations in terms

of percentage of carbon in the compound.


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Activity 20.3

ORGANIC CHEMISTRY

Aim: To test for alkenes with bromine

Apparatus:Test tube

Materials:Liquid bromineHexene

Procedure:

1. Add about 2 cm 3 of liquid bromine in a test tube.

2. Then, add about 2 cm 3 of hexene to the liquid bromine.

3. Shake the mixture gently.

4. Observe the colour changes that take place in the test tube.

Results:

1. The brown colour of liquid bromine is ...

2. State the molecular formula of hexene: .

3. Write the equation for the addition of bromine to hexene.

4. Name the product of addition of bromine to hexene.


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Activity 20.4

ORGANIC CHEMISTRY

Aim: To compare the flammability and the colour of the flame produced by different alcohols and

to show the variation of physical properties of the first four alcohols.

Apparatus:Evaporating dishesWooden splint

Bunsen burner

Materials:MethanolEthanolPropanol

ButanolCobalt(II) chloride paper

Procedure:1. Pour a little of each of the following alcohols (methanol, ethanol, propanol and butanol) into

four different evaporating dishes.

2. Burn the alcohols with the lighted wooden splint.

3. Compare the colour of the flame and the ease of it burning.

4. Observe what is left on the evaporating dishes. Test it with blue cobalt(II) chloride paper.


Evaporating dish

Methanol


Evaporating dish

Ethanol


Evaporating dish

Propanol


Evaporating dish

Butanol


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Questions:

1. Note the differences of the colour of the flames from the burning of methanol to butanol.

Explain this variation.

2. Which alcohol is the most flammable?

3. Work out the molecular masses of the four alcohols.

Alcohol Molecular mass

Methanol

Ethanol

Propanol

Butanol

4. How is the flammability of the alcohols related to their molecular masses?


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Activity 20.5

ORGANIC CHEMISTRY

Aim: To compare fluidity of the alcohols.


Materials:MethanolEthanol

PropanolButanol

Procedure:1. Half fill the four test tubes with four different alcohols and compare their fluidity.

2. Place the order of fluidity among the four alcohols.

Results:

most fluid least fluid1 2 3 4

Questions:

As the molecular mass increases the alcohols become . fluid.


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Activity 20.6

ORGANIC CHEMISTRY

Aim: To show oxidation of ethanol to ethanoic acid.

Apparatus:Bunsen burnerBoiling tubeTest tube

Retort stand with clampBeakerDelivery tube

Materials:EthanolPotassium dichromate(VI) solutionDilute sulphuric acid

Cold waterBlue litmus paper

Procedure:

1. The boiling tube is filled with approximately 5 3cm of potassium dichromate(VI) solution.

2. About 5 3cm of dilute sulphuric acid is added to the potassium dichromate(VI) solution.

3. About 5 3cm of ethanol is added to the acidified potassium dichromate(VI) solution.

4. A rubber stopper fitted with a delivery tube is inserted into the boiling tube. The delivery tube is

inserted into a test tube placed in a beaker half-filled with cold water.

5. The mixture of ethanol and acidified potassium dichromate(VI) is boiled slowly. The distillate is

collected in the test tube.6. Observe the colour change of acidified potassium dichromate(VI) to show that oxidation of

ethanol to ethanoic acid has taken place.

7. The colour and the odour of the distillate are recorded.

8. The distillate is tested with a piece of blue litmus paper.

Test tube

Distillate

Cold water

Boiling tube

Mixture of ethanol andacidified potassiumdichromate(VI)


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Results:

Test on the distillate Observations

Colour

Smell

Action on blue litmus paper

Questions:

1. When ethanol is boiled with acidified potassium dichromate(VI) solution, it is oxidised to

ethanoic acid which has the smell of ..

2. The colour of acidified potassium dichromate changes from . to

..


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Activity 20.7

ORGANIC CHEMISTRY

Aim: To show acidic properties of carboxylic acid.

Apparatus:Evaporating dishTripod standBunsen burnerSpatula

Wooden splintsTest tubesGlass rodDelivery tube

Materials:Ethanoic acid

Aqueous sodium hydroxideSodium carbonate powder

Magnesium ribbonLimewaterRed litmus paper

Procedure:

(a) Reaction of ethanoic acid with sodium hydroxide

1. About 10 3cm of ethanoic acid is poured into an evaporating dish.

2. Drop a piece of red litmus paper into the evaporating dish to act as indicator.

3. Slowly add sodium hydroxide solution to the ethanoic acid until the red litmus paper just turns

blue.

4. Remove the litmus paper and heat the solution mixture until dryness.

Observations:

Describe the product left behind the evaporating dish after the solution mixture is evaporated to

dryness.

...

.............................................................................................................................................................


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(b) Reaction between ethanoic acid with magnesium ribbon

1. The test tube is filled with about 5 3cm of ethanoic acid.

2. A piece of magnesium ribbon (about 3 cm long) is added to ethanoic acid.

3. Test the gas given off with the lighted wooden splint.

Observations:

...

(c) Reaction between ethanoic acid with sodium carbonate

1. About 5 3cm of ethanoic acid is added to a test tube.

2. A spatula of sodium carbonate powder is added to the ethanoic acid.3. The gas released is passed into limewater.

Observations:

...


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REFERENCES:

1. T.Y. Toon, L.W. Leng & T.O Tin. Success Chemistry SPM. Selangor Darul Ehsan: Oxford

Fajar Sdn. Bhd, 2007.

2. Practical Chemsitry For O Level. Singapore: Dyna Publisher Pte. Ltd.3. C.N. Prescott. Chemistry A Course for O Level. Practical Workbook. Volume 1. Singapore:

Federal Publications (S) Pte Ltd, 1994.

4. C.N. Prescott. Chemistry A Course for O Level. Practical Workbook. Volume 2. Singapore:

Federal Publications (S) Pte Ltd, 1994.

5. L.J. Rasanayagam. Practical Chemistry. A course for O Level. Volume 1. Singapore: Federal

Publications (S) Pte Ltd, 1981.

6. L.J. Rasanayagam. Practical Chemistry. A course for O Level. Volume 2. Singapore: Federal

Publications (S) Pte Ltd, 1981.

7. J.G.R. Briggs. Chemistry O Level Practical. Volume 1 (2nd Ed.). Singapore: Pearson

Education Asia Pte Ltd, 1998.

8. J.G.R. Briggs. Chemistry O Level Practical. Volume 2 (2nd Ed.). Singapore: Pearson

Education Asia Pte Ltd, 1998.

9. T.Y. Toon & C.L. Kwong. Chemistry Matters for GCE O Level. Practical Workbook.

Singapore: Times Media Private Limited, 2002.

10. L.J. Rasanayagam & R.M. Kok. GCE O Level Chemistry Matters. Practical Book. Singapore:

Marshall Cavendish Education, 2007.

11. R.M. Heyworth & J.G.R. Briggs. Chemistry Insights O Level (2nd Ed.) Practical Workbook.

Singapore: Pearson Education South Asia Pte Ltd, 2007.

activity resources (teacher's edition) - 2 years

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