1. SULIT 4541/3
1
1. Diagram shows three sets, Set I, Set II and Set III, of the apparatus set-up for an experiment to
compare the reactivity of alkali metals towards oxygen.
(a) State one hypothesis for this experiment.
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[3 marks]
(b) Record the observation for Set III in the above diagram.
[3 marks]

2. SULIT 4541/3
2
(c) Construct a table to record the observations for Set I, Set II and Set III.
[3 marks]
(d) Based on the observation in Set III, predict metal X.
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[3 marks]
(e) Diagram shows the pH meter readings when the metal oxides formed in Set I, Set II and Set
III were dissolved in water.

3. SULIT 4541/3
3
Record the pH value to one decimal place for Set I, Set II and Set III.
Set I: _________________________________________________________________
Set II: _________________________________________________________________
Set III: _________________________________________________________________
[3 marks]
(f) Based on the above diagram, complete the table below.
Manipulated variable:
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Method to manipulate the variable:
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Responding variable:
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How the variable is responding:
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Fixed variable:
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Method to maintain the fixed variable:
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[6 marks]

4. SULIT 4541/3
4
2. Diagram shows Step I and Step II in an experiment to construct an ionic equation for the
formation of barium chromate(VI).
0.5 mol dm-3
barium chloride, BaCl2 solution was added to each test tube containing 5.0 cm3
potassium chromate(VI), K2CrO4 solution according to the volumes shown in Step II. Each test
tube is stoppered and shaken well. Yellow precipitate of barium chromate(VI) is formed.
Table shows the results for this experiment.
Test tube 1 2 3 4 5 6 7
Volume of 0.5 mol dm-3
barium chloride
solution/cm3
1.0 2.0 3.0 4.0 5.0 6.0 7.0
Height of barium chromate(VI) precipitate/cm

5. SULIT 4541/3
5
(a) Using a ruler, measure the height of yellow precipitate in test tubes 1 to 7 and record the
height of the precipitate in the above table.
[3 marks]
(b) Draw a graph of height of precipitate against volume of barium chloride on the graph paper
provided.
[3 marks]
(c) Based on the graph in 2(b), state the volume of barium chloride solution 0.5 mol dm-3
for
reacts completely with 5 cm3
of potassium chromate(VI) solution and calculate the number of
moles of barium chloride solution needed to react completely with the potassium
chromate(VI) solution.
[3 marks]
(d) Write an ionic equation for the reaction between potassium chromate(VI) solution and barium
chloride solution.
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[1 mark]
(e) State the operational definition for the precipitation of barium chromate(VI).
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[2 marks]

6. SULIT 4541/3
6
3. The reaction between zinc and sulphuric acid will produce zinc sulphate and hydrogen gas. The
chemical equation for the reaction is shown below:
Zn + H2SO4  ZnSO4 + H2
Referring to the information above, plan a laboratory experiment to investigate the effect of size
of zinc on the rate of reaction.
Your planning should include the following aspects:
(a) Problem statement
(b) Hypothesis
(c) All the variables
(d) List of materials and apparatus
(e) Procedure
(f) Tabulation of data
[17 marks]
END OF QUESTION PAPER