a) Coke reduces lead (II) oxide to metal lead
b) Limestone produces calcium oxide which combines with Silica to form calcium silicate hence removes silica impurities
c) Scrap iron reduces any remaining lead sulphide to lead metal
johnmulu answered the question on February 21, 2017 at 07:33
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The basic raw material for extraction of aluminium is bauxite.
a) Name the method that is used to extract aluminium from bauxite
b) Write the chemical formula of the major component of bauxite
c) i) Name two major impurities in bauxite
ii) Explain how the impurities in bauxite are removed
d) cryolite is used in extraction of aluminium from bauxite. State its function
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Date posted: February 21, 2017. Answers (1)
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Date posted: February 21, 2017. Answers (1)
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Iron is extracted from its ore by the blast furnace process
a) Name one ore from which iron is extracted.
b) One of the impurities in iron is removed in the form of calcium silicate. Write an equation for the reaction in which calcium silicate is produced.
Date posted: February 21, 2017. Answers (1)
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a) Suggest one method that can be used to extract element J from its oxide
b) Arrange the elements H, J and carbon in the order of their decreasing reactivity.
Date posted: February 21, 2017. Answers (1)
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Date posted: February 21, 2017. Answers (1)
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Date posted: February 21, 2017. Answers (1)
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and state the advantage of using duralumin in place of aluminium for manufacture of aeroplane n parts
(Solved)
a) Explain why it is not advisable to use wood ash for cleaning aluminium utensils
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Date posted: February 21, 2017. Answers (1)
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Date posted: February 21, 2017. Answers (1)
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Date posted: February 20, 2017. Answers (1)
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Date posted: February 18, 2017. Answers (1)
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Date posted: February 18, 2017. Answers (1)
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Date posted: February 18, 2017. Answers (1)
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Date posted: February 16, 2017. Answers (1)
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During the electrolysis of aqueous silver nitrate, a current of 5.0 A was passed through the electrolyte for 3 hours.
a) Write the equation for the reaction which took place at the anode
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Date posted: February 16, 2017. Answers (1)
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b) Name the product formed at the cathode.
Date posted: February 16, 2017. Answers (1)
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State how the following substances conduct electricity:
i) Molten calcium chloride
ii) Graphite
Date posted: February 16, 2017. Answers (1)
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Date posted: February 16, 2017. Answers (1)
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When a current of 0.82 A was passed for 5 hours through an aqueous solution of metal Z, 2.65 g of the metal were deposited. (1 Faraday = 96500 Coulombs: Relative atomic mass of Z = 52)
(a) Calculate the number of faradays used.
(b) Determine the charge on the ion of metal P.
(c) Write the equation for the formation of ion of P.
Date posted: February 16, 2017. Answers (1)
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Brine usually contains soluble calcium and magnesium salts. Explain how sodium carbonate is used to purify brine
Date posted: February 16, 2017. Answers (1)