151.Boron and silicon of very high purity can be obtained through- (1)vapour phase refining
- (2)electrolytic refining
- (3)liquation
- (4)zone refining
152.In the extraction of copper from its sulphide ore, the metal is finally obtained by the reduction of cuprous oxide with- (1)carbon monoxide
- (2)copper (I) sulphide
- (3)sulphur dioxide
- (4)iron (II) sulphide.
153.During the process of electro-refining of copper some metals present as impurity settle as anode mud. These are :- (1)Sn and Ag
- (2)Pb and Zn
- (3)Ag and Au
- (4)Fe and Ni
154.Calamine and Malachite, respectively, are the ores of :- (1)Nickel and Aluminium
- (2)Zinc and Copper
- (3)Copper and Iron
- (4)Aluminium and Zinc
155.The metal that can be purified economically by fractional distillation method is:- (1)Fe
- (2)Zn
- (3)Cu
- (4)Ni
156.Which of the following pairs of metals is purified by van Arkel method ?- (1)Ga and Ιn
- (2)Zr and Ti
- (3)Ag and Au
- (4)Ni and Fe
157.Which ofthe following pairs ofmetals is purified by van Arkel method?- (1)Ga and In
- (2)Zr and Ti
- (3)Ag and Au
- (4)Ni and Fe(2011)
158.Given below are two statements : Statement I : According to the Ellingham diagram, any metal oxide with higher ∆G0 is more stable than the one with lower ∆G0. Statement II : The metal involved in the formation of oxide placed lower in the Ellingham diagram can reduce the oxide of a metal placed higher in the diagram. In the light of the above statements, choose the most appropriate answer from the options given below:- (1)Both Statement I and Statement II are correct.
- (2)Both Statement I and Statement II are incorrect
- (3)Statement I is correct but Statement II is incorrect.
- (4)Statement I is incorrect but Statement II is correct.
159.Which one of the following is a mineral of iron?- (1)Malachite
- (2)Cassiterite
- (3)Pyrolusite
- (4)Magnetite(2012)
160.Which one is malachite from the following- (1)CuCO3.Cu(OH)2
- (2)CuFeS2
- (3)Cu(OH)2
- (4)Fe3O4
161.Which one of the following statements is incorrect ?- (1)Boron and Indium can be purified by zone refining method.
- (2)Van- Arkel method is used to purify tungsten.
- (3)Cast iron is obtained by melting pig iron with scrap iron and coke using hot air blast.
- (4)The malleable iron is prepared from cast iron by oxidising impurities in a reverberatory furnace.
162.The major components in "Gun Metal" are:- (1)Al, Cu, Mg and Mn
- (2)Cu, Sn and Zn
- (3)Cu, Zn and Ni
- (4)Cu, Ni and Fe
163.The method of zone refining of metals is based on the principle of- (1)greater mobility of the pure metal than that of the impurity
- (2)higher melting point of the impurity than that of the pure metal
- (3)greater noble character of the solid metal than that of the impurity
- (4)greater solubility of the impurity in the molten state than in the solid.
164.The following reactions take place in the blast furnace in the preparation of impure iron. Identify the reaction pertaining to the formation of the slag.- (1)Fe2O3(s)+3CO(g)→2Fe(l)+3CO2(g)
- (2)CaCO3(s)→CaO(s)+CO2(g)
- (3)CaO(s)+SiO2(s)→CaSiO3(s)
- (4)2C(s)+O2(g)→2CO(g) (Mains2011)
165.The element that can be refined by distillation is- (1)gallium
- (2)nickel
- (3)zinc
- (4)tin
166.Which of the reaction is suitable for concentrating ore by leaching process ?- (1)2Cu2S + 3O2 →2Cu2O + 2SO2
- (2)Fe3O4 + CO → 3FeO + CO2
- (3)A12O3 + 2NaOH + 3H2O → 2Na[A1(OH)4
- (4)A12O3 + 6Mg → 6MgO + 4A1
167.The method used for the purification of Indium is :- (1)van Arkel method
- (2)vapour phase refining
- (3)zone refining
- (4)Liquation
168.The metal that is not extracted from its sulphide ore is :- (1)Aluminium
- (2)Iron
- (3)Lead
- (4)Zinc
169.Which of the following taking place in the Blast furnace is endothermic?- (1)CaCO3→CaO+CO2
- (2)2C+O2→2CO
- (3)C+O2→CO2
- (4)Fe2O3+3CO→2Fe+3CO2
170.The metal purified by Mond process is X and metal purified by van Arkel method is Y. X and Y respectively are- (1)Ni,Zr
- (2)Mn,Ti
- (3)Zr,Ti
- (4)Ni,Cu
171.In the extraction of copper from its sulphide ore, the metal is formed by reduction of Cu2O with- (1)FeS
- (2)CO
- (3)Cu2S
- (4)SO2
172.According to the following diagram, A reduces BO2 when the temperature is :- (1)< 1200ºC
- (2)> 1200ºC but < 1400ºC
- (3)< 1400ºC
- (4)> 1400ºC
173.Heating mixture of Cu2O and Cu2S will give :- (1)Cu2SO3
- (2)CuO + CuS
- (3)Cu + SO3
- (4)Cu + SO2
174.Purest form of commercial iron is:- (1)Wrought iron
- (2)Cast iron
- (3)Pig iron
- (4)Iron scrap + pig iron
175.Hall-Heroult’s process is given by :- (1)2Al2O3 + 3C → 4Al + 3CO2
- (2)Cu+2 (aq) + H2(g) → Cu(s) + 2H+(aq)
- (3)ZnO + C Zn + CO
- (4)Cr2O3 + 2Al → Al2O3 + 2Cr
176.Blister copper is- (1)impure Cu
- (2)Cu alloy
- (3)pure Cu
- (4)copper having 1% impurity
177.Ellingham diagram is drawn between- (1)change in potential of pH
- (2)change in free energy and oxidation state
- (3)change in free energy and temperature
- (4)change in free energy and polarisability
178.Identify the incorrect statement- (1)The scientific and technological process used for isolation of the metal from its ore is known as metallurgy
- (2)Minerals are naturally occurring chemical substances in the earth’s crust
- (3)Ores are minerals that may contain a metal
- (4)Gangue is an ore contaminated with undesired materials
179.Cassiterite is an ore of- (1)Sb
- (2)Ni
- (3)Mn
- (4)Sn (1999)
180.The method, which is based on the principle that "different components of a mixture are differently adsorbed on an adsorbent" is called- (1)zone refining method
- (2)vapour phase refining method
- (3)liquation method
- (4)chromatographic method
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