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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
Name the following:
A metal oxide that can be reduced by hydrogen.
Complete the following by selecting the correct option from the choices given:
The metal whose oxide, which is amphoteric, is reduced to metal by carbon reduction ____________. (Fe/Mg/Pb/Al)
Give equation for the following conversion:Aluminium to sodium aluminate.
Give the chemical name and formula of 'cryolite'
Name a non-metallic element which forms acidic and neutral oxides
With reference to the reduction of copper (II) oxide , iron (II) oxide, lead (II) oxide and magnesium oxide; place the oxides in order of increasing ease of reduction.[i.e. first write the oxide that is most difficult to reduce and at last, the oxide, that is most easily reduced.]
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.
Answer the following question :
Name the process used for the enrichment of sulphide ore.
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 metal whose oxide, which is amphoteric, is reduced to metal by carbon reduction ________
