a) The ore is roasted to convert iron to iron (II) oxide. The oxide then reacts with silicon (IV) oxide to form iron (II) silicate which separates out as slag.
b)- Sulphur (IV) oxide produced causes air pollution
- Mining of the ore from the ground causes land degradation
johnmulu answered the question on February 21, 2017 at 08:19
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Aluminium is both malleable and ductile
a) What is meant by?
i) Malleable
ii) Ductible
b) State one use of alumunium based on:
i) Malleability
ii) Ductility
Date posted: February 21, 2017. Answers (1)
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Date posted: February 21, 2017. Answers (1)
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a) Coke
b) Limestone
c) Scrap iron.
Date posted: February 21, 2017. Answers (1)
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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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Date posted: February 21, 2017. Answers (1)
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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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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 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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Date posted: February 16, 2017. Answers (1)
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State how the following substances conduct electricity:
i) Molten calcium chloride
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Date posted: February 16, 2017. Answers (1)