acids,bases & salts-p6 - smart edu hub |...

0620/61/M/J/10© UCLES 2010 [Turn over

ForExaminer’s

Use

5 Solid E was analysed. E was an aluminium salt.The tests on the solid and some of the observations are in the following table.Complete the observations in the table.

tests observationstests on solid E

(a) Appearance of solid E. white crystalline solid

(b) A little of solid E was heated in atest-tube.

colourless drops of liquid formed at the top of the tube

(c) A little of solid E was dissolved in distilledwater.

The solution was divided into fourtest-tubes and the following tests werecarried out.

(i) To the fi rst test-tube of solution, dropsof aqueous sodium hydroxide wereadded. Excess sodium hydroxide was thenadded to the test-tube.

(ii) Test (i) was repeated using aqueousammonia solution instead of aqueoussodium hydroxide.

(iii) To the third test-tube of solution,dilute hydrochloric acid was added,followed by barium chloride solution.

(iv) To the fourth test-tube of solution,aqueous sodium hydroxide andaluminium powder were added.The mixture was heated.

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

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

............................................................ [3]

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

........................................................... [2]

no reaction

effervescencepungent gas given off

turned damp litmus paper blue

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ACIDS,BASES & SALTS-P6

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ForExaminer’s

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5 Solid E was analysed. E was a calcium salt. The tests on the solid and some of the observations are in the following table. Complete the observations in the table.

tests observationstests on solid E

(a) Appearance of solid E. white crystalline solid

(b) A little of solid E was heated in a test-tube.

colourless drops of liquid formed at the top of the tube

(c) A little of solid E was dissolved in distilled water.

The solution was divided into fourtest-tubes and the following tests were carried out.

(i) To the fi rst test-tube of solution, drops of aqueous sodium hydroxide were added.

Excess sodium hydroxide was then added to the test-tube.

(ii) Test (i) was repeated using aqueous ammonia solution instead of aqueous sodium hydroxide.

(iii) To the third test-tube of solution, dilute hydrochloric acid was added followed by barium chloride solution.

(iv) To the fourth test-tube of solution, aqueous sodium hydroxide and aluminium powder were added.

The mixture was heated.

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

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

............................................................ [3]

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

........................................................... [1]

no reaction

effervescencepungent gas given off

turned damp litmus paper blue

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0620/63/M/J/10© UCLES 2010

ForExaminer’s

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(d) What does test (b) tell you about solid E.

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

..................................................................................................................................... [1]

(e) What does test (c)(iii) tell you about solid E?

..................................................................................................................................... [1]

(f) Identify the gas given off in test (c)(iv).

..................................................................................................................................... [1]

(g) What conclusions can you draw about solid E?

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

..................................................................................................................................... [2]

[Total: 9]

94

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0620/61/M/J/11© UCLES 2011

ForExaminer’s

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4 A student investigated the reaction between two different solutions of deep purple potassium manganate(VII), A and B, and an acidic solution of hydrogen peroxide.

Three experiments were carried out.

Experiment 1

A burette was fi lled with the solution A of potassium manganate(VII) up to the 0.0 cm3 mark. Using a measuring cylinder, 25 cm3 of colourless hydrogen peroxide solution was poured into the conical fl ask.

The potassium manganate(VII) solution A was added slowly to the fl ask, and shaken to mix thoroughly. Addition of potassium manganate(VII) solution was continued until there was a permanent pink colour in the contents of the fl ask.

(a) Use the burette diagram to record the volume in the table of results and complete the column. [2]

31

32

33

final reading

Experiment 2

Experiment 1 was repeated using the solution B of potassium manganate(VII) instead of solution A.

(b) Use the burette diagrams to record the volumes in the table of results and complete the table. [2]

18

19

20

initial reading

34

35

36

final reading

experiment 1 experiment 2

fi nal reading / cm3

initial reading / cm3

difference / cm3

95

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ForExaminer’s

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Experiment 3

To a little of the hydrogen peroxide solution in a test-tube, manganese(IV) oxide was added.

Rapid effervescence was observed and a glowing splint relit.

(c) Identify the gas given off in Experiment 3.

..................................................................................................................................... [1]

(d) (i) What colour change was observed when potassium manganate(VII) solution was added to the fl ask?

from ..................................................... to ..................................................... [1]

(ii) Why was an indicator not added to the fl ask?

.............................................................................................................................. [1]

(e) (i) In which experiment was the greatest volume of potassium manganate(VII) solution used?

.............................................................................................................................. [1]

(ii) Compare the volumes of potassium manganate(VII) used in Experiments 1 and 2.

.............................................................................................................................. [1]

(iii) Suggest an explanation for the difference in volumes.

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

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

.............................................................................................................................. [2]

(f) If Experiment 2 was repeated using 12.5 cm3 of the hydrogen peroxide solution, what volume of potassium manganate(VII) solution would be needed to react completely? Explain your answer.

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

..................................................................................................................................... [3]

(g) Give one advantage and one disadvantage of using a measuring cylinder for the hydrogen peroxide solution.

advantage .........................................................................................................................

disadvantage .............................................................................................................. [2]

[Total: 16]

96

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0620/61/M/J/11© UCLES 2011

ForExaminer’s

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5 Two different liquids, M and N, were analysed. N was aqueous potassium iodide. The tests on the liquids and some of the observations are in the following table. Complete the observations in the table.

tests observations

(a) (i) Appearance of liquid M.

(ii) Appearance of liquid N.

colourless liquid with an antiseptic smell

............................................................ [2]

(b) (i) A few drops of M were transferred to a dry watch glass. The liquid was touched with a lighted splint.

(ii) Test (b)(i) was repeated using liquid N.

(c) A little of liquid M was added to a crystal of iodine in a test-tube. The test-tube was shaken.

(d) To a little of liquid N, a few drops of dilute nitric acid was added, followed by silver nitrate solution.

burns with a yellow fl ame

............................................................ [1]

orange-brown solution

........................................................... [2]

(e) What type of substance is liquid M?

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

..................................................................................................................................... [2]

[Total: 7]

97

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0620/63/M/J/11© UCLES 2011

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5 A mixture, Z, of two different solids was analysed. Z consisted of solid W, which waswater-soluble ammonium chloride, and solid V, which was insoluble.

The tests on the solids, and some of the observations, are in the following table.

Complete the observations in the table.

tests observationstests on mixture Z

(a) Appearance of the mixture. white solid

Mixture Z was added to distilled water in a boiling tube. The boiling tube and contents were shaken and then fi ltered.

tests on the fi ltrate

The fi ltrate was divided into three test-tubes.

(b) (i) To the fi rst test-tube of the fi ltrate, a few drops of dilute nitric acid was added followed by silver nitrate solution.

(ii) To the second test-tube of the fi ltrate, aqueous sodium hydroxide was added.

The mixture was heated. The gas given off was tested with damp pH indicator paper.

(iii) To the third test-tube of the fi ltrate, dilute hydrochloric acid was added followed by barium chloride solution.

............................................................ [2]

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

........................................................... [2]

........................................................... [1]

105

105

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ForExaminer’s

Usetests observations

tests on the residue

(c) By using a spatula, some of the residue was transferred from the fi lter paper into a test-tube. Dilute hydrochloric acid was added to the residue.

The gas given off was tested.

The solution in the test-tube was divided into two portions.

rapid effervescence

limewater turned milky

(d) (i) To the fi rst portion of the solution, excess aqueous sodium hydroxide was added.

(ii) To the second portion of the solution, excess aqueous ammonia solution was added.

white precipitate formed,insoluble in excess

no precipitate formed

(e) Identify the gas given off in (c).

..................................................................................................................................... [1]

(f) What conclusions can you draw about solid V?

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

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

..................................................................................................................................... [2]

[Total: 8]

106

106

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0620/63/M/J/12© UCLES 2012

ForExaminer’s

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5 A mixture of two solids, G and H, was analysed. G was water-soluble and H was copper carbonate.

The tests on the mixture and some of the observations are in the following table. Complete the observations in the table.

tests observations

The mixture was added to water in a boiling tube. The mixture was shaken and fi ltered. The fi ltrate and the residue were tested.


(a) To the fi ltrate, dilute nitric acid was added followed by aqueous silver nitrate. white precipitate

(b) To the fi ltrate, dilute sulfuric acid was added. white precipitate


(c) A little of the residue was put into atest-tube and dilute nitric acid added.

The gas was tested.

The contents of the test-tube were kept for test (d).

................................................................... [1]

................................................................... [2]

(d) The contents of the test-tube were divided into two portions.

(i) To the fi rst portion, an excess of aqueous sodium hydroxide was added.

(ii) To the second portion, a few drops of aqueous ammonia were added.

Excess aqueous ammonia was then added.

................................................................... [2]

................................................................... [1]

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

................................................................... [2]

(e) What conclusions can you draw about solid G?

..................................................................................................................................... [2]

[Total: 10]

108

108

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0620/61/M/J/13© UCLES 2013

ForExaminer’s

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4 A mixture of two solids, E and F, was analysed. Solid E was the water-soluble salt aluminium chloride, Al Cl 3, and solid F was an insoluble

salt. The tests on the mixture and some of the observations are in the following table. Complete the observations in the table.

tests observations

Distilled water was added to the mixture in a boiling tube.The contents of the boiling tube were shaken and fi ltered, keeping the fi ltrate and residue for the following tests.


The fi ltrate was divided into fi ve portions in fi ve test-tubes.

(a) The fi rst portion was used to describe the appearance of the fi ltrate. appearance ........................................ [1]

(b) Several drops of aqueous sodium hydroxide were added to the second portion of the solution.

Excess aqueous sodium hydroxide was then added to the test-tube.

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

............................................................ [3]

(c) Aqueous ammonia was added to the third portion, dropwise and then in excess.

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

............................................................ [2]

(d) To the fourth portion of the solution, dilute nitric acid and aqueous silver nitrate were added. ............................................................ [2]

(e) To the fi fth portion of the solution, about 1 cm3 of dilute nitric acid and barium nitrate solution were added. ............................................................ [1]

113

113

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ForExaminer’s

Usetests observations


(f) (i) To a little of the residue, dilutehydrochloric acid was added.

The gas given off was tested.

(ii) The residue was heated, gently then strongly.

rapid effervescence

gas turned limewater milky

solid changed colour from green to black

(g) What conclusions can you draw about solid F?

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

..................................................................................................................................... [2]

[Total: 11]

114

114

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ForExaminer’s

Use4 Two solids, H and I, were analysed. H was the salt copper ethanoate, (CH3COO)2Cu. The tests on the solids and some of the observations are in the following table. Complete the observations in the table.

tests observations

tests on solid H

Solid H was added to distilled water in atest-tube and shaken to dissolve. The solution was divided into three equal portions intest-tubes, and the following tests carried out.

(a) Appearance of the solution. ................................................................... [1]

(b) Aqueous sodium hydroxide was added to the second portion of the solution. ................................................................... [2]

(c) Drops of aqueous ammonia were added to the third portion of the solution.

Excess aqueous ammonia was then added to the mixture.

................................................................... [2]

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

................................................................... [2]

tests on solid I

(d) (i) Solid I was heated in a dry test-tube. The gas given off was tested with a lighted splint.

The test-tube was left to cool. Dilute hydrochloric acid was then

added to the test-tube. The gas given off was tested.

(ii) Solid I was added to dilute nitric acid in a test-tube. The solution was warmed and the mixture smelled.

solid turned black and charredthe gas ignited

effervescence

limewater turned milky

smell of vinegar

(e) What conclusions can you draw about solid I?

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

..................................................................................................................................... [2]

[Total: 9]

120

120

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0620/61/M/J/14© UCLES 2014

5 A solid U was analysed. U was a soluble metal sulfate. The tests on U, and some of the observations are in the following table. Complete the observations.

tests observations

tests on solid U

(a) Appearance of solid U. pink crystals

(b) Solid U was heated gently and then strongly in a test-tube. condensation droplets formed on the sides of the test-tube

(c) Solid U was added to distilled water in a test-tube and shaken until dissolved.

The solution was divided into three equal portions in separate test-tubes and the following tests carried out.

Several drops of aqueous sodium hydroxide were added to the fi rst portion of the solution and thetest-tube shaken.

Then hydrogen peroxide solution was added to the mixture and the gas given off tested.

pale brown precipitate

effervescenceglowing splint relit

(d) Dilute nitric acid was added to the second portion of the solution followed by barium nitrate solution.

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

...................................................................................... [2]

(e) Dilute nitric acid was added to the third portion of the solution followed by silver nitrate solution. ...................................................................................... [1]

129

129

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(f) What does test (e) tell you about solid U?

.............................................................................................................................................. [1]

(g) Name the gas given off in test (c).

.............................................................................................................................................. [1]

(h) What conclusions can you draw about solid U?

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

.............................................................................................................................................. [2]

[Total: 7]

130

130

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5 Two solids, P and Q, were analysed. P was a metal compound and Q was calcium iodide. Tests were carried out on P and Q and some of the observations are in the following table. Complete the observations for solid Q.

tests observations

tests on solid P

(a) Appearance of solid P. black solid

(b) (i) Dilute sulfuric acid was added to solid P and the mixture warmed.

The solution was divided into two equal portions in test-tubes.

The following tests were carried out.

(ii) Drops of aqueous sodium hydroxide were added to the fi rst portion of the solution.

Excess sodium hydroxide was then added to the mixture in the test-tube.

(iii) Aqueous ammonia was added to the second portion of the solution until no further change was seen.

the solid reacted and a blue solution was formed

blue precipitate formed

blue precipitate insoluble

blue precipitate formed which dissolvedto form a deep blue solution

136

136

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0620/63/M/J/14© UCLES 2014

tests observations

tests on solid Q

(c) Distilled water was added to solid Q and the mixture shaken to dissolve solid Q.

The solution was divided into three equal portions in separate test-tubes.

(i) Aqueous sodium hydroxide was added to the fi rst portion until no further change was seen.

(ii) Aqueous ammonia was added to the second portion until no further change was seen.

(iii) Dilute nitric acid and aqueous silver nitrate were added to the third portion.

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

..................................................................................... [3]

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

..................................................................................... [1]

..................................................................................... [1]

(d) Identify solid P.

.............................................................................................................................................. [2]

[Total: 7]

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0620/61/M/J/15© UCLES 2015

5 Solid C was analysed. Solid C was a mixture of salts containing aluminium ions, sulfate ions and another cation (positive ion).

Tests on solid C, and some of the observations, are in the table. Complete the observations in the table.

tests observations

tests on solid C

(a) Appearance of solid C. white solid

(b) A little of solid C was heated gently and then strongly.

The gas given off was tested with damp pH indicator paper.

condensation was formed at the top of the test-tube

pungent gas, pH = 10

tests on a solution of C

Water was added to solid C to produce an aqueous solution, solution C.

(c) Drops of aqueous sodium hydroxide were added to solution C using a teat pipette.

Excess aqueous sodium hydroxide was then added to the mixture.

The mixture was boiled gently and any gases given off were tested.

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

...................................................................................... [3]

pungent gas, pH = 10

(d) Excess aqueous ammonia was added to solution C. ...................................................................................... [1]

(e) A few drops of dilute nitric acid and aqueous silver nitrate were added to solution C. ...................................................................................... [1]

(f) A few drops of dilute nitric acid and barium nitrate solution were added to solution C. ...................................................................................... [2]

143

143

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(g) What does the formation of condensation in test (b) tell you about the nature of solid C?

.............................................................................................................................................. [1]

(h) What does test (e) tell you about the nature of solid C?

.............................................................................................................................................. [1]

(i) (i) Name the gas given off in test (b).

....................................................................................................................................... [1]

(ii) What is your conclusion about the identity of the other cation in solid C?

....................................................................................................................................... [1]

[Total: 11]

144

144

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5 Solid H was analysed. Solid H was a salt containing iron(III) ions, sulfate ions and one other cation (positive ion).

The tests on solid H, and some of the observations are in the following table. Complete the observations in the table.

tests observations

tests on solid H

(a) Appearance of solid H. pale yellow solid

(b) Solid H was heated gently and then strongly.

The gas given off was tested with pH indicator paper.

condensation formed at the top of the test-tube

pungent gas

pH paper turned blue-green, pH 10

tests on a solution of H

Water was added to solid H to produce an aqueous solution, solution H.

(c) Drops of aqueous sodium hydroxide were added to 1 cm3 of solution H and the test-tube shaken.

Excess sodium hydroxide was then added to the test-tube.

The mixture was heated gently and the gas given off was tested.

...................................................................................... [2]

...................................................................................... [1]

pungent gas, red litmus paper turned blue

(d) Excess aqueous ammonia solution was added to solution H. ...................................................................................... [1]

(e) Dilute nitric acid and aqueous silver nitrate were added to solution H. ...................................................................................... [1]

(f) Dilute nitric acid and barium nitrate solution were added to solution H. ...................................................................................... [2]

148

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0620/63/M/J/15© UCLES 2015

(g) What does the formation of condensation in test (b) tell you about the nature of solid H?

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

.............................................................................................................................................. [1]

(h) What does test (e) tell you about the nature of solid H?

.............................................................................................................................................. [1]

(i) (i) Name the gas given off in test (c).

....................................................................................................................................... [1]

(ii) What conclusions can you draw about the identity of the other cation in solid H?

....................................................................................................................................... [1]

[Total: 11]

149

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0620/62/F/M/15© UCLES 2015

5 Two metal salt solutions, E and F, were analysed. E was a mixture of iron(II) sulfate and ammonium sulfate. The tests on the solutions and some of the observations are in the following table. Complete the observations in the table.

tests observations

tests on solution E

(a) Appearance of solution E. ................................................................ [1]

The solution was divided into three equal portions in separate test-tubes.

(b) Dilute nitric acid and aqueous barium nitrate were added to the fi rst portion of the solution. ................................................................ [1]

(c) (i) Excess aqueous sodium hydroxide was added to the second portion of the solution.

(ii) The mixture was fi ltered and the fi ltrate heated.

The gas given off was tested with damp litmus paper.

................................................................ [2]

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

................................................................ [2]

(d) Dilute sulfuric acid and aqueous potassium manganate(VII), an oxidising agent, were added to the third portion of the solution.

Aqueous sodium hydroxide was then added to the mixture. ................................................................ [1]

tests on solution F

(e) Appearance of solution F. yellow liquid

(f) Zinc powder was added to solution F.

The solution was observed for fi ve minutes.

The gas given off was tested with a splint.

rapid effervescence

turned blue, then green and fi nally light purple

lighted splint popped

157

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0620/62/F/M/15© UCLES 2015 [Turn over

(g) Identify the gas given off in test (f).

.............................................................................................................................................. [1]

(h) What conclusions can you draw about solution F?

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

.............................................................................................................................................. [2]

[Total: 10]

158

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0620/61/O/N/10© UCLES 2010 [Turn over

ForExaminer’s

Use

5 Two different solutions, X and Y, were analysed. X was copper sulfate solution. The tests on the solutions, and some of the observations, are in the following table.

Complete the observations in the table.

tests observationstests on solution X

(a) (i) Appearance of solution X.

(ii) To a little of solution X, aqueous sodium hydroxide was added.

(iii) To a little of solution X, aqueous ammonia was added drop by drop and shaken.

Excess aqueous ammonia solution was then added to the test-tube.

................................................................ [1]

................................................................ [2]

................................................................ [1]

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

................................................................ [2]

tests on solution Y

(b) (i) A little of solution Y was tested with Universal Indicator paper. The pH was recorded.

(ii) To about 3 cm3 of solution Y a few drops of dilute hydrochloric acid and then aqueous barium chloride wasadded.

pH1

white precipitate

(c) Identify solution Y.

..................................................................................................................................... [2]

[Total: 8]

159

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0620/63/O/N/10© UCLES 2010

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5 Two salts, W and X, were analysed. X was iron(II) chloride. The tests on each salt, and some of their observations, are in the following table. Complete the observations in the table.

tests observationstests on salt W

(a) A little of W was heated in a test-tube. Any gas given off was tested with damp pH indicator paper.

a white solid formed at the top of thetest-tube

pungent gas evolved, pH 8-10

(b) W was dissolved in distilled water in atest-tube.

The solution was divided into three portions in test-tubes and the following tests carried out.

(i) To the fi rst portion, dilute hydrochloric acid was added and then aqueous barium chloride.

(ii) To the second portion, dilute nitric acid was added and then aqueous silver nitrate.

(iii) To the third portion, aqueous sodium hydroxide was added. The mixture was heated and any gases given off were tested with damp pH indicator paper.

white precipitate

no visible reaction

pungent gas evolved, pH 8-10

tests on salt X

(c) Appearance of salt X.

(d) Salt X was dissolved in distilled water in a test-tube. The solution was divided into two portions.

(i) To the fi rst portion, excess aqueous sodium hydroxide was added.

(ii) To the second portion, a few drops of nitric acid was added followed by aqueous silver nitrate.

................................................................. [1]

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

................................................................. [2]

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

................................................................. [2]

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(e) Identify the gas given off in tests (a) and (b)(iii).

..................................................................................................................................... [1]

(f) What conclusions can you draw about salt W?

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

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

..................................................................................................................................... [3]

[Total: 9]

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0620/63/O/N/10© UCLES 2010

ForExaminer’s

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7 The label shows the substances present in a bottle of orange fruit drink.

ORANGE FRUIT DRINK

Contains: orange juice, malic acid, citric acidand natural colours (carotenes)

NO ARTIFICIAL COLOURS (E NUMBERS)

(a) A piece of pH indicator paper was dipped in the drink.

(i) Predict the pH value obtained.

.............................................................................................................................. [1]

(ii) Why does the pH indicator paper give a more reliable result than adding Universal Indicator solution to the drink?

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

.............................................................................................................................. [1]

(b) Describe an experiment you could carry out to show that only natural colours were present in the drink.

A space has been left if you want to draw a diagram to help you answer the question.

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

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

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

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

..................................................................................................................................... [4]

[Total: 6]

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0620/61/O/N/11© UCLES 2011

ForExaminer’s

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2 A student prepared a sample of potassium nitrate by neutralising nitric acid using potassium hydroxide solution.

25.0 cm3 of nitric acid was poured into a conical fl ask. Potassium hydroxide was added a little at a time from a burette as shown below.

potassium hydroxidesolution

nitric acid

After each addition of potassium hydroxide solution the pH was measured with a pH meter and the values recorded in the table of results.

volume of potassium hydroxidesolution added / cm3 pH value

5.0 1.2

10.0 1.4

15.0 2.6

20.0 2.0

24.0 2.7

24.5 3.0

25.5 11.0

26.0 11.3

30.0 12.0

40.0 13.2

You are going to draw a graph to fi nd the volume of potassium hydroxide solution required to neutralise the 25.0 cm3 of nitric acid.

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(a) Plot the results on the grid below and draw a smooth line graph.

14

12

10

8

6

4

2

00 5 10 15 20

volume of potassium hydroxidesolution added / cm3

25 30 35 40

pH

[3]

(b) Which point appears to be inaccurate?

..................................................................................................................................... [1]

(c) (i) Use your graph to fi nd the pH of the solution when 35.0 cm3 of potassium hydroxide was added.

.............................................................................................................................. [1]

(ii) Use your graph to fi nd the pH of 25.0 cm3 of nitric acid.

Show clearly on the grid how you obtained your answer.

.............................................................................................................................. [2]

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0620/61/O/N/11© UCLES 2011

ForExaminer’s

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(d) (i) What is the pH of the solution when all of the nitric acid has just been neutralised?

.............................................................................................................................. [1]

(ii) What volume of potassium hydroxide was required to neutralise 25.0 cm3 of nitric acid?

.............................................................................................................................. [1]

(e) Describe how the student should modify the experiment to obtain pure crystals of potassium nitrate.

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

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

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

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

..................................................................................................................................... [3]

[Total: 12]

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ForExaminer’s

Use

5 Three different liquids P, Q and R were analysed. P was an aqueous solution of sulfuric acid. The tests on the liquids and some of the observations are in the following table. Complete the observations in the table.

tests observations

(a) (i) Appearance of the liquids.

(ii) The pH of the liquids was tested using Universal Indicator paper.

P ............................................................... [1]

Q colourless, smell of vinegar

R colourless, no smell

P ............................................................... [1]

Q pH 5

R pH 7

(b) A piece of magnesium ribbon was added to a little of each liquid.

The gas given off by liquid P was tested.

P .....................................................................

................................................................... [2]

Q slow effervescence

R no reaction

(c) To a little of liquid P, hydrochloric acid and aqueous barium chloride were added. ................................................................... [2]

(d) Liquid R was heated to boiling in atest-tube. A thermometer was used to record the constant temperature of the vapour produced.

temperature = 100 °C

(e) What conclusions can you draw about liquid Q?

..................................................................................................................................... [2]

(f) Identify liquid R.

..................................................................................................................................... [1]

[Total: 9]

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5 Two metal salt solutions, X and Y, were analysed. Solution X was iron(II) chloride. The tests on X and Y, and some of the observations, are given in the following tables. Complete the observations in the table.

tests observations

tests on solution X

(a) Appearance of solution X. ...................................................................................... [1]

The solution was divided into four equal portions.

(b) Dilute nitric acid and aqueous silver nitrate were added to the fi rst portion of solution. ...................................................................................... [1]

(c) Aqueous sodium hydroxide was added to the second portion of solution and the mixture shaken. ...................................................................................... [2]

(d) Excess aqueous ammonia was added to the third portion of solution. ...................................................................................... [1]

(e) An oxidising agent was added to the fourth portion of the solution.

Aqueous sodium hydroxide was then added to the mixture. ...................................................................................... [2]

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tests observations

tests on solution Y

The solution was divided into three equal portions.

(f) Dilute hydrochloric acid was added to the fi rst portion of the solution. white precipitate formed

(g) Aqueous sodium hydroxide was added to the second portion of the solution and the mixture shaken.

Aluminium powder was added to the mixture and it was warmed gently. The gas given off was tested with damp red litmus paper.

effervescence

pungent gas evolved, litmus paper turned blue

(h) Aqueous potassium iodide was added to the third portion of the solution. pale yellow precipitate

(i) What conclusions can you draw about solution Y?

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

.............................................................................................................................................. [2]

[Total: 9]

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5 Two solids, P and Q, were analysed. Q was anhydrous copper(II) sulfate. Tests on the solids and some of the observations are in the following tables. Complete the observations in the table.

tests observations

tests on solid P

(a) Appearance of solid P. white crystals

(b) Solid P was heated gently in a dry test-tube. condensation formed at the top of the test-tube

tests on aqueous solution of P

An aqueous solution of P was divided into three equal portions.The following tests were carried out.

(c) The pH of the fi rst portion of the solution was tested. pH 5

(d) Copper(II) oxide was added to the second portion of the solution. The mixture was boiled and the mixture left to stand for one minute. blue solution formed

(e) Magnesium powder was added to the third portion of the solution. The mixture was shaken and the gas evolved tested. effervescence, lighted splint popped

(f) Identify the gas in test (e).

.............................................................................................................................................. [1]

(g) What conclusions can you draw about solid P?

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

.............................................................................................................................................. [2]

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tests observations

tests on solid Q

(h) Appearance of solid Q. ...................................................................................... [1]

(i) Solid Q was added to distilled water and stirred with a thermometer. The temperature of the mixture was measured and recorded after one minute.

temperature change ...........................................................

other observations ..............................................................

...................................................................................... [2]

The solution formed was divided into two equal portions.

(j) An equal volume of aqueous sodium hydroxide was added to the fi rst portion of the solution. ...................................................................................... [2]

(k) Drops of aqueous ammonia were added to the second portion of the solution and shaken.

Excess ammonia solution was then added.

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

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

...................................................................................... [3]

[Total: 11]

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