Page 473 - SUBSEC October 2017_Neat
P. 473

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                           (iii)   What is the volume of KMnO  (aq) / H  (aq) to be used for calculation?
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                                                              4
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                           (v)    Calculate the concentration of the Fe   ions in the given solution in g dm .
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                           (vi)   Calculate the percentage purity of the sample.
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                    (b)    Outline the steps that you would take to prepare 1 dm of the iron (II) sulphate solution.
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                                                                                                   [4 marks]


                    (c)    State why it is not usually good practice to store iron (II) sulphate for extended periods of time
                           after its bottle has been opened.

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                                                                                                    [1 mark]

                                                                                              Total 15 marks
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