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प्रश्न
Write the names and chemical formulae of any ‘two’ minerals of aluminium.
उत्तर
1) Bauxite → `Al_2O_3 .2H_2O`
2) Cryolite → `Na_3AlF_6`
APPEARS IN
संबंधित प्रश्न
Write the names and chemical formulae of any one ore of iron.
The process of leaching alumina, using sodium carbonate is called
- Bayer's process
- Decomposition
- Cyanide process
- Hall's process
Write the reactions involved in the zone of reduction in blast furnace during extraction of iron.
Silica is added to roasted copper ore during smelting process to remove _______.
(A) ferrous sulphide
(B) ferrous oxide
(C) cuprous sulphide
(D) cuprous oxide
Out of C and CO, which is a better reducing agent at the lower temperature range in the blast furnace to extract iron from the oxide ore?
Fe2O3 is reduced to spongy iron near the top of blast furance by
(A) H2
(B) CaO
(C) SiO2
(D) CO
Mention names and formulae of two ores of alumunium.
Draw neat and labelled diagram of Bessermer converter used in the extraction of copper.
What is the role of coke in the extraction of iron from its oxides?
What is the role of silica in the extraction of copper?
Which of the ores mentioned can be concentrated by magnetic separation method?
The chemical formula of willemite is __
(a) ZnS
(b) ZnCO3
(c) ZnO
(d) Zn2SiO4
What is the role of the following compound-
SiO2 in the extraction of copper from copper pyrites?
In the extraction of zinc from zinc blende:
(i) Give an equation to show how zinc oxide is converted to zinc.
(ii) How is impure zinc finally electro-refined?
Complete the following statement by selecting the correct alternative from the choices given:
A current liberates 0.50 g of hydrogen in 2 hours. The weight of copper (at. wt. = 63.5) deposited at the same time by the same current through copper sulphate solution is: ___________
Bauxite has the composition
Give the uses of zinc.
Metals which occur in their native state in nature:
Which among the following statement is correct?
Carbonate ore of iron is ____________.
In the extraction of aluminium by Hall-Heroult process, purified \[\ce{Al2O3}\] is mixed with \[\ce{CaF2}\] to:
(i) lower the melting point of \[\ce{Al2O3}\].
(ii) increase the conductivity of molten mixture.
(iii) reduce \[\ce{Al^{3+}}\] into \[\ce{Al(s)}\].
(iv) acts as catalyst.
Which of the following reactions occur during calcination?
(i) \[\ce{CaCo3 -> CaO + CO2}\]
(ii) \[\ce{2FeS2 + 11/2 O2 -> Fe2O3 + 4SO2}\]
(iii) \[\ce{Al2O3. {x}H2O -> Al2O3 + {x}H2O}\]
(iv) \[\ce{ZnS + 3/2 O2 -> ZnO + SO2}\]
Although carbon and hydrogen are better reducing agents but they are not used to reduce metallic oxides at high temperatures. Why?
Write the chemical reactions involved in the extraction of gold by cyanide process. Also give the role of zinc in the extraction.
Native silver metal forms a water solution complex with dilute solution of Na CN in the presence of
Which of the following is not an ore of magnesiuim?
Pyrolusite is ______.
