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प्रश्न
What is the role of the following compound-
SiO2 in the extraction of copper from copper pyrites?
उत्तर
Role of SiO2 in the extraction of copper from copper pyrites:
- The copper matte containing Cu2S and FeS is put in silica lined converter in order to remove impurities as fusible slag. Som silica is also added and hot air blast is blown to convert remaining FeS to FeO, which is removed as slag with silica.
\[\ce{\underset{\text{Ferrous sulphide}}{2FeS} + \underset{\text{From blast of hot air}}{3O_2} -> \underset{\text{Ferrous oxide}}{2FeO} + \underset{\text{Sulphur dioxide}}{2SO_2}}\] - Ferrous oxide combines with silica (flux) to form fusible slag.
\[\ce{\underset{\text{Ferrous oxide}}{FeO} + \underset{\text{Silica (Flux)}}{SiO_2} -> \underset{\text{Ferrous silicate (Fusible slag)}}{FeSiO_3}}\]
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संबंधित प्रश्न
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
Write chemical formulae of the following ores :
(a) Calamine
(b) Haematite
(c) Magnetite
(d) Corundum
Draw neat and labelled diagram of Bessermer converter used in the extraction of copper.
Purification of aluminium by electrolytic refining is carried out by
(a)Hoope process
(b)Hall process
(c)Baeyer process
(d)Serperck process
What is the role of limestone in the extraction of iron from its oxides?
Describe the roles of the following: SiO2 in the extraction of copper from copper matte
Which of the ores mentioned can be concentrated by magnetic separation method?
Define Leaching.
Explain the following methods to protect metals from corrosion:
Passivation
Draw a neat, well labelled diagram of electrolytic cell for extraction of aluminium
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?
What happens when a nickel rod is dipped into a copper sulphate solution? Justify your answer.
`[E_((Ni^(+2))/(Ni))^0 = -0.25"v" and E _(("Cu"^(+2))/("Cu"))^0 = +0.34"v"]`
Describe the role of the Cryolite in the extraction of aluminium from pure alumina.
Give the uses of zinc.
Which of the following options are correct?
(i) Cast iron is obtained by remelting pig iron with scrap iron and coke using hot air blast.
(ii) In extraction of silver, silver is extracted as cationic complex.
(iii) Nickel is purified by zone refining.
(iv) Zr and Ti are purified by van Arkel method.
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?
The important ore of iron is:-
In the electrolytic process for the extraction of aluminium the electrolyte is:-
Which of the following is not ore of aluminium?
Metal always found in Free State is
In the extraction of iron, the slag produce is
Pyrolusite is ______.
Match List I with List II.
List - I | List - II | ||
a. | Siderite | I. | FeCO3 |
b. | Malachite | II. | CuCO3 · Cu(OH)2 |
c. | Sphalerite | III. | ZnS |
d. | Calamine | IV. | ZnCO3 |
Choose the correct answer from the option given below.