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प्रश्न
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.
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उत्तर
(i) Cast iron is obtained by remelting pig iron with scrap iron and coke using hot air blast.
(iv) Zr and Ti are purified by van Arkel method.
Explanation:
Iron obtained from blast is called pig iron. It contains about 4% carbon and many impurities such as Mn, P, Si, etc. The pig iron is remelted with scrap iron. This is known as cast iron. It has slightly less carbon content (3%) and is extremely hard and brittle.
\[\ce{\underset{Impure}{Zr(s)} + 2I2 ->[870K] ZrI4(g) ->[2705K][tungsten filament] \underset{Pure}{Zr(s)} + 2I2}\]
\[\ce{Ti + 2I2 ->[530K] Ti4 ->[1700K] Ti + 2I2}\]
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संबंधित प्रश्न
Write the reactions involved in the zone of reduction in blast furnace during extraction of iron.
Write chemical formulae of the following ores :
(a) Calamine
(b) Haematite
(c) Magnetite
(d) Corundum
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 CO in the extraction of Iron?
What is the role of silica in the extraction of copper?
Define leaching.
Which among the following minerals does NOT contain aluminium?
(a) Cryolite
(b) Siderite
(c) China clay
(d) Corundum
The chemical formula of willemite is __
(a) ZnS
(b) ZnCO3
(c) ZnO
(d) Zn2SiO4
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?
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 ______.
What happens when a nickel rod is dipped into a copper sulphate solution? Justify your answer.
[\[\ce{E{^{\circ}_{Ni^{+2}/Ni}}}\] = − 0.25 V and \[\ce{E{^{\circ}_{Cu^{+2}/Cu}}}\] = +0.34 V]
Give the uses of zinc.
Which among the following statement is correct?
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.
Identify a mineral for the major source of boron from the following list?
Extraction of zinc from zinc blende is achieved by:-
Metal always found in Free State is
When compared to ΔG° for the formation of Al2O3 ΔG° for the formation of Cr2O3 is
Which of the following statements, about the advantage of roasting of sulphide ore before reduction is not true?
