C1.17a Extracting metals from their ores: Student brief Practice Controlled Assessment This practice controlled assessment is about extracting metals from their ores. Some metals can be extracted from their ores by heating with carbon. These are metals which are lower in the reactivity series. Metals which are found higher in the reactivity series cannot be extracted by heating with carbon and can be extracted by electrolysis. You are going to test the hypothesis that some metals can be extracted from their ores by heating with carbon. Plan an investigation to test what happens when a selection of metal ores are heated with carbon.
Part A: Planning How to attempt the task: You must produce a plan. The plan must include: •
an explanation of which equipment you need to complete the task. You may want to draw a diagram of how the equipment will be set up
•
which variable (or variables) you will change and which you will keep the same
•
which measurements you should make to test the hypothesis, explaining how these will test the hypothesis, and including the number and range of measurements
•
any risks that are linked to the practical task and how you can reduce these to make your practical task safer.
You should check that the overall plan is clear and will produce a range of results that will test the hypothesis.
Part B: Observations You are going to test the hypothesis that some metals can be extracted from their ores by heating with carbon. You will test this hypothesis using your own method from Part A. You should also collect some secondary evidence on extracting metals from their ores.
How to attempt the task: You should decide on the number and range of measurements you will make Complete the practical task, recording your measurements clearly and accurately Collect some secondary evidence on this task Comment on the quality of the source of this secondary evidence.
Part C: Conclusions You will need your primary and secondary evidence from the Part B: Observations task and information about the method you used.
How to attempt the task: You must process your primary and secondary evidence from Part B and present these, using mathematical processes if relevant. You must produce a conclusion in which you: •
review all of the primary and secondary evidence, then identify and deal with any anomalies
•
draw conclusions from this processed evidence to prove or disprove a hypothesis
•
show how the data supports the conclusion
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explain how you might change the method if you were going to repeat the investigation
•
describe the primary and secondary evidence you might collect to extend your investigation and say why you would collect it.
© Pearson Education 2010. Edexcel GCSE Science Activity Pack This document may have been altered from the original.
C1.17b Extracting metals from their oxides: Observations Practice Controlled Assessment Copper oxide, iron oxide, magnesium oxide and lead oxide are examples of ores. You are going to test the hypothesis that some metals can be extracted from their ores by heating with carbon. You will be given the following equipment/resources: iron oxide lead oxide TOXIC copper oxide HARMFUL magnesium oxide
Bunsen burner beaker (small) spatula pipe clay triangle
mat and tripod crucible tongs powdered charcoal
Health and safety •
Eye protection should be worn.
•
Take care with hot apparatus.
•
Hold the crucible with tongs. Grip the crucible with one side of the tongs inside the crucible and one side outside the crucible.
•
Copper compounds are HARMFUL.
•
Lead compounds are TOXIC.
How to tackle the task: You should decide on the number and range of observations you will make. Complete the practical task, recording your observations clearly and making sure that you produce good quality data.
Follow these instructions when carrying out the practical: 1
Place one spatula load of copper oxide in a crucible.
2
Add two spatula loads of powdered charcoal (a form of carbon) and stir it with the spatula to mix it with the copper oxide.
3
Add a thin layer of powdered charcoal over the surface of the mixture.
4
Place the crucible in a pipe clay triangle on a tripod with a Bunsen burner and mat.
crucible
tripod and gauze
5
Heat the mixture strongly for a few minutes.
6
Stop heating and allow the mixture to cool down.
7
Observe the crucible and look for evidence of any changes.
8
Using tongs, tip the contents of the crucible into the beaker that is half filled with water.
9
Stir the water. The dense metal should sink to the bottom with other substances floating at the top.
10 Repeat this process with other metal oxides if you think you need to.
© Pearson Education 2010. Edexcel GCSE Science Activity Pack This document may have been altered from the original.
heatproof mat
C1.17c Extracting metals from their oxides: Recording results Practice Controlled Assessment Name
Class
Date
Carry out the investigation on worksheet C1.17b Extracting metals from their ores: Observations and use this sheet to record your results and draw a conclusion.
Recording your results 1
Put your observations for this experiment in the table below. Metal oxide
Was metal formed?
Observations that suggest that the metal was formed
Considering your results/conclusions 2
Which metals did you extract from their oxides? __________________________________________________________________
3
How could you tell that a metal had been extracted from its oxide? __________________________________________________________________ __________________________________________________________________
4
What conclusion can you draw about the different metals? __________________________________________________________________ __________________________________________________________________
5
Which other metals do you think could be extracted from their oxides? Give reasons for your answer. __________________________________________________________________ __________________________________________________________________
Evaluation 6
How easy was it to tell if a metal had been formed. Explain your answer. __________________________________________________________________ __________________________________________________________________
7
How would you improve your investigation so that you could be more certain about your conclusion? __________________________________________________________________ __________________________________________________________________
8
Explain how any improvements would improve your investigation.
Š Pearson Education 2010. Edexcel GCSE Science Activity Pack This document may have been altered from the original.