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Question
- A to F below relate to the source and extraction of either zinc or aluminium:
- Bauxite
- Coke
- Cryolite
- Froth floatation
- Sodium hydroxide solution
- Zinc blende
- Write down the three letters each from the above list which are relevant to
- Zinc
- Aluminium
- Fill in the blanks using the most appropriate words from A to F.
- The ore from which aluminium is extracted must first be treated with ………………. so that pure aluminium oxide can be obtained.
- Pure aluminium oxide is dissolved in ….. to make a conducting solution.
iii. Write the formula of cryolite.
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Solution
a.
i.
1.Zinc
Zinc blende, Froth flotation, Coke
2.Aluminium
Cryolite, Bauxite, Sodium hydroxide solution
b.
ii.
1. The ore from which aluminium is extracted must first be treated with sodium hydroxide solution so that pure aluminium oxide can be obtained.
2. Pure aluminium oxide is dissolved in cryolite to make a conducting solution.
iii.The formula of cryolite is Na3AlF6.
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