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प्रश्न
The process of leaching alumina, using sodium carbonate is called
- Bayer's process
- Decomposition
- Cyanide process
- Hall's process
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उत्तर
Hall’s process
In Hall’s process, the ore and sodium carbonate are fused to convert aluminium oxide into soluble sodium meta aluminate.
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संबंधित प्रश्न
Silica is added to roasted copper ore during smelting process to remove _______.
(A) ferrous sulphide
(B) ferrous oxide
(C) cuprous sulphide
(D) cuprous oxide
Fe2O3 is reduced to spongy iron near the top of blast furance by
(A) H2
(B) CaO
(C) SiO2
(D) CO
What is the role of cryolite in the extraction of aluminium?
What is the role of limestone in the extraction of iron from its oxides?
Which form of the iron is the purest form of commercial iron?
Name the method used for refining of copper metal.
Differentiate between “minerals” and “ores”.
Define leaching.
Write the names and chemical formulae of any ‘two’ minerals of aluminium.
Which among the following minerals does NOT contain aluminium?
(a) Cryolite
(b) Siderite
(c) China clay
(d) Corundum
Draw a neat, well labelled diagram of electrolytic cell for extraction of aluminium
Why does copper obtained in the extraction from copper pyrites have a blistered appearance?
Copper has the face centred cubic structure. The coordination number of each ion is:
How will you convert the following:
[Ag(CN)2]− to Ag
Metals which occur in their native state in nature:
Metal which is found in free state is:
The sulphide ore of iron is ____________.
When copper ore is mixed with silica, in a reverberatory furnace copper matte is produced. The copper matte contains ______.
The main reactions occurring in blast furnace during extraction of iron from haematite are:
(i) \[\ce{Fe2O3 + 3CO -> 2Fe + 3CO2}\]
(ii) \[\ce{FeO + SiO2 -> FeSiO3}\]
(iii) \[\ce{Fe2O3 + 3C -> 2Fe + 3CO}\]
(iv) \[\ce{CaO + SiO2 -> CaSiO3}\]
Although carbon and hydrogen are better reducing agents but they are not used to reduce metallic oxides at high temperatures. Why?
When a strip of metallic zinc is placed in an aqueous solution of copper nitrate the blue colour of the solution disappear due to formation of
In the thermite process, the reducing agent is:
In the electrolytic process for the extraction of aluminium the electrolyte is:-
Metal always found in Free State is
Pyrolusite is ______.
Calamine and Malachite, respectively, are the ores of ______.
