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प्रश्न
- 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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उत्तर
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.
संबंधित प्रश्न
Give appropriate scientific reasons for Zinc oxide can be reduced to zinc metal by using
carbon, but aluminium oxide cannot be reduced by a reducing agent
An element L consists of molecules.
When L is heated with iron metal, it forms a compound, FeL. What chemical term would you use to describe the change undergone by L?
Explain with reason:
In the electrolytic reduction of alumina, the graphite anode is gradually consumed.
Give reason for the following:
Carbon anodes are used in the electrolytic extraction of aluminium.
Give equation for the following conversion:Aluminium to sodium aluminate.
Name oxide of one metal which is reduced by (give equation): Electrolytic reduction
In order to obtain one tone of aluminium, the following inputs are required:
4 tones of bauxite, 150 Kg of sodium hydroxide and 600 Kg of graphite.
The aluminium compound in bauxite is aluminium oxide and the main impurity is iron (II) oxide. Aluminium is obtained by the electrolysis of aluminium oxide dissolved in cryolite.
(i) Write the formula of cryolite.
(ii) Write down the word which correctly completes the following sentence.
"By dissolving aluminium oxide in cryolite, a ______ (conducting / non- conducting) solution is produced.
(iii) Why so much graphite required for this electrolytic process.
(iv) Write the equation for the reaction which takes place at cathode.
Name the following :
A metal oxide that can be reduced by hydrogen
Answer the following question with respect by hydrogen : Identify the components of the electrolyte other than pure alumina and the role played by each.
Name two metallic oxides which cannot be reduced by carbon, carbon monoxide or hydrogen.
