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प्रश्न
Define Leaching.
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उत्तर
Leaching:
Leaching is the process of extracting a soluble material from an insoluble solid by dissolving out in a suitable solvent.
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संबंधित प्रश्न
Write the names and chemical formulae of any one ore of zinc.
The process of leaching alumina, using sodium carbonate is called
- Bayer's process
- Decomposition
- Cyanide process
- Hall's process
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.
Indicate the principle behind the method used for the refining of zinc.
Differentiate between “minerals” and “ores”.
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
What is the role of the following compound-
SiO2 in the extraction of copper from copper pyrites?
Copper has the face centred cubic structure. The coordination number of each ion is:
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 ______.
Give the uses of zinc.
Metal which is found in free state is:
Which among the following statement is correct?
The most abundant metal on earth is:
The sulphide ore of iron is ____________.
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) \[\ce{ZnS + 3/2 O2 -> ZnO + SO2}\]
Identify a mineral for the major source of boron from the following list?
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 | ||
| 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.
Calamine and Malachite, respectively, are the ores of ______.
The ore that contains both iron and copper is ______.
