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प्रश्न
what is the function of cryolite in the extraction of aluminium, other than acting as a solvent for bauxite?
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उत्तर
Cryolite is used in the electrolysis of alumina. The function of cryolite is to
(i) Reduce melting point of alumina
(ii) Make molten alumina a good conductor of electricity.
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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
Give reason for the following:
Carbon anodes are used in the electrolytic extraction of aluminium.
Give the chemical name and formula of ‘cryolite’.
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.
Complete the following by selecting the correct option from the choices given :
The diavalent metal whose oxide is reduced to metal by electrolysis of its fused salt is ________
Write the observation for the following:
A paper dipped in potassium permanganate solution is put on the mouth of a test tube containing sulphur dioxide gas.
- 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.
Steel is an alloy of iron and ______.
Name two metallic oxides which cannot be reduced by carbon, carbon monoxide or hydrogen.
