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प्रश्न
Write the name.
Extraction of aluminium from alumina-
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उत्तर
Electrolytic reduction
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संबंधित प्रश्न
How many carats is pure gold? Why is pure gold not suitable for making ornaments?
Explain why, carbon cannot reduce oxides of sodium or magnesium.
Why does aluminium not corrode right through?
How is zinc extracted from its carbonate ore (calamine)? Explain with equations.
Explain giving one example, how highly reactive metals (which are high up in the reactivity series) are extracted.
How are the less reactive metals (which are quite low in the reactivity series) extracted? Explain with the help of an example.
Name the metal which is extracted from the ore called ‘rock salt’.
Name two ores of zinc. Write the names of the chemical compounds present in them and give their chemical formulae.
Name one ore of mercury. Which mercury compound is present in this ore? Write its chemical formula.
Which of the following metals can be obtained from haematite ore?
Zinc blende ore can be converted into zinc oxide by the process of ______.
Which metal can be extracted from the following ore?
Calamine
Give reasons, why aluminum is used in:
In aluminiothermy
Identify the process given in following passage and draw neat labelled diagram showing the process.
Electrolysis of molten mixture of alumina (melting point > 20000C) is done in a steel tank. The tank has a graphite lining on the inner side. This lining does the work of a cathode. A set of graphite rods dipped in the molten electrolyte works as anode. Cryolite (Na3AlF6) and fluorspar (CaF2) are added in the mixture to lower its melting point upto 10000C.
State one observation for each of the following :
Copper sulphate solution is electrolysed using copper electrodes.
To protect iron from rusting, it is coated with a thin layer of zinc. Name the process.
Write the molecular formulae of the following compound.
Sodium aluminate
Observe the following diagram and write answers.
- Name the method.
- Write anode reaction and cathode reaction.
- Why fluorspar and cryolite are added in the mixture?
During extraction of metals, electolytic refining is used to obtain pure metals.
(a) Which material will be used as anode and cathode for refining of silver metal by this process?
(b) Suggest a suitable electrolyte also.
(c) In this electrolytic cell, where do we get pure silver after passing electric current?
The given reaction shows one of the processes to extract the metals like Iron and Manganese.
\[\ce{MnO2(s) + Al(s) -> Mn(l) + Al2O3(s) + Heat}\]
Give the reason why the above reaction is known as a thermite reaction.
