Advertisements
Advertisements
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
Advertisements
उत्तर
(B) ferrous oxide
APPEARS IN
संबंधित प्रश्न
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.
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 cryolite in the extraction of aluminium?
In the extraction of Al, impure Al2O3 is dissolved in conc. NaOH to form sodium aluminate and leaving impurities behind. What is the name of this process?
What is the role of coke 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?
Differentiate between “minerals” and “ores”.
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?
Metals which occur in their native state in nature:
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) \[\ce{ZnS + 3/2 O2 -> ZnO + SO2}\]
Write the chemical reactions involved in the extraction of gold by cyanide process. Also give the role of zinc in the extraction.
The important ore of iron is:-
In the thermite process, the reducing agent is:
Metal always found in Free State is
When compared to ΔG° for the formation of Al2O3 ΔG° for the formation of Cr2O3 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.
Calamine and Malachite, respectively, are the ores of ______.
The ore that contains both iron and copper is ______.
