YEAR 11 PRACTICAL
ASSESSMENT TEST 2012
Chemistry
Name: _________________________
Time allowed: 50 minutes
Total Marks: 30
Instructions
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Attempt all questions at each of three stations.
Answer all questions in the spaces provided.
Please leave all equipment as you found it before moving onto the next station.
Bring a calculator (they will not be provided).
A periodic table will be provided for this test.
There are 3 stations. You are allowed 16 minutes for each station.
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STATION 1 SEPARATING A MIXTURE DATA ANALYSIS (10 marks)
A group of students was supplied with a mixture of three solids - copper (II) oxide, iron and
sodium sulfate. They were asked to gather data about these substances so that they could design
a method of separating them. The data they gathered is shown below.
Substance
Colour
Solubility in water
(g /100g water)
Melting point (°C)
Density (g cm-3)
Magnetic properties
Reaction with dilute
sulfuric acid
copper (II) oxide
black
iron
red-brown
sodium sulfate
white
0
0
19.4
decomposes
6.4
non-magnetic
dissolves to form a blue
solution of copper (II)
sulfate
1435
magnetic
dissolves slowly
producing hydrogen gas
and a pale green solution
884
2.7
non-magnetic
dissolves without
reaction
(a) The formula to determine the density of a substance is:
density = mass
volume
A sample of 17.8 g of iron metal was found to have a volume of 2.2 cm3. Calculate the
density of this sample and write this figure in the missing space in your table.
(2 marks)
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(b) The students proposed method of separating the three components of the mixture is shown below
but they are not in the correct order. Write the numbers of the following 7 steps in the correct order.
Separation steps (not in the correct order)
Note: A filtrate is what passes through filter paper. A residue is what does not pass through the filter paper.
1. Stir the powdered mixture repeatedly with a bar magnet.
2. Grind the solid mixture using a mortar and pestle and put the powdered mixture in
a small beaker.
3. Slowly evaporate the filtrate in an evaporating basin and collect the dry sodium sulfate crystals.
4. Add a small volume of water to the remaining solids and stir with a glass rod to dissolve the
sodium sulfate.
5. Place the copper (II) oxide residue and filter paper on a clock glass and dry in the air.
6. Filter the mixture through a filter paper.
7. Remove the magnet covered in iron powder and deposit the powder in a Petri dish.
Numbers in correct order: ______________________________________________________ (4 marks)
(c) Identify any of the steps of the method 1 to 7 that involve ‘chemical’ separation methods.
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(d) The students performed an additional procedure to recover pure copper from the original
mixture. Their collected data is recorded below.
(2 marks)
(2 marks)
mass of powdered mixture = 5.0 g
mass of copper recovered = 0.47 g
Use this data to determine the percentage by weight of copper in the mixture.
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STATION 2 THE PHYSICAL PROPERTIES OF ELEMENTS (10 marks)
At this station you are provided with:
 two elements X and Y;
 a bottle of hydrochloric acid (HCl);
 a test-tube rack with large test tubes;
 a small measuring cylinder and
 equipment to set up an electrical circuit.
Experiment A
 Place 5 mL of hydrochloric acid in a large test tube
 Add a strip of element X to the liquid in the test tube
1. Observe the reaction and write down two pieces of evidence to show that a chemical reaction
has taken place.
(2 marks)
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Experiment B
 Use the equipment provided to test sample X and Y for electrical conductivity
 Examine both elements for lustre (how shiny they are) and for malleability.
2. Put your results in the form of a table in the space below.
(3 marks)
3. A student decided that element Y was aluminium.
(5 marks)
(a) Write the electron configuration of aluminium ___________________________
(b) Write an equation to show the formation of an ion of aluminium from an aluminium atom.
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(c) State one use of aluminium and a property that makes it suitable for that use.
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STATION 3 THERMAL DECOMPOSITION (10 marks)
Safety issues
 Wear safety glasses and an apron throughout
this experiment.
 Take care not to touch the hot test tube.
Complete the following Experiment
1. Place one teaspoon of copper carbonate in one
test tube and half-fill another test tube with limewater.
2. Set up the apparatus as shown in the drawing opposite.
3. Heat the copper carbonate gently at first and then
strongly using a blue Bunsen flame.
4. Allow the gas produced to bubble into the tube of
limewater and observe any changes.
5. After several minutes, and while still heating the copper carbonate, remove the tube of limewater
and place it in a test-tube rack. This stops limewater entering the hot test tube.
6. Continue to heat the copper carbonate for about another 3 minutes.
7. Turn off the Bunsen burner and allow the tube and contents to cool.
Questions
1. Record all your experimental observations in the table below.
(2 marks)
Observations
2. Explain any changes to the limewater.
(1 mark)
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3. The powder that forms after heating copper (II) carbonate is copper (II) oxide.
Use the data book supplied to complete the following information.
Copper (II) carbonate
(3 marks)
Copper (II) oxide
Formula
Colour
Melting point (oC)
4. Write a correct equation using chemical formulae for this decomposition reaction.
(no states required).
(2 marks)
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5. Write a brief conclusion for this experiment.
(2 marks)
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