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प्रश्न
Write the names and chemical formulae of any one ore of zinc.
उत्तर
The important ores of zinc are
zinc blende ZnS,
Calamine ZnCO3,
Zincite ZnO and
Willemite Zn2SiO4.
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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
Write chemical formulae of the following ores :
(a) Calamine
(b) Haematite
(c) Magnetite
(d) Corundum
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?
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?
What is the role of CO in the extraction of Iron?
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?
Differentiate between “minerals” and “ores”.
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
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: ___________
How will you convert the following:
[Ag(CN)2]− to Ag
Bauxite has the composition
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?
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
The important ore of iron is:-
Which of the following is not ore of aluminium?
Metal always found in Free State is
When compared to ΔG° for the formation of Al2O3 ΔG° for the formation of Cr2O3 is
Pyrolusite is ______.
Match List - I with List - II.
| List - I | List - II | ||
| (One) | (Composition) | ||
| (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 options given below:
Calamine and Malachite, respectively, are the ores of ______.
The ore that contains both iron and copper is ______.
