JEE Chemistry General Principles and Processes Of Isolation Of Elements MCQs Set B

Question: In the extraction of copper from its sulphide ore, the metal is finally obtained by the reduction of cuprous oxide with

• a) Copper (I) sulphide (Cu₂S)
• b) Sulphur dioxide (SO₂)
• c) Iron sulphide (FeS)
• d) Carbon monoxide (CO)

Answer: Copper (I) sulphide (Cu₂S)

Question: Extraction of zinc from zinc blende is achieved by

• a) roasting followed by reduction with carbon
• b) electrolytic reduction
• c) roasting followed by reduction with another metal
• d) roasting followed by self-reduction

Answer: roasting followed by reduction with carbon

Question: In the extraction of Cu, the metal is formed in the bessemer converter due to the reaction

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: Aluminothermic process is used for the extraction of metals, whose oxides are

• a) not easily reduced by carbon
• b) fusible
• c) not easily reduced by hydrogen
• d) strongly basic

Answer: not easily reduced by carbon

Question: Electrometallurgical process is used to extract

• a) Na
• b) Fe
• c) Pb
• d) Ag

Answer: Na

Question: The electrolytic method of reduction is employed for the preparation of metals that

• a) are strongly electropositive
• b) form oxides
• c) are moderately electropositive
• d) are weakly electropositive

Answer:  are strongly electropositive

Question: Aluminium is extracted from alumina (Al₂O₃ ) by electrolysis of a molten mixture of

• a)

  

• b)

  

• c) Both
• d) None of these

Answer:

Question: In the extraction of aluminium by Hall-Heroult process, purified Al₂O₃ is mixed with CaF₂ to

(i) lower the melting point of Al₂O₃.
(ii) increase the conductivity of molten mixture.
(iii) reduce Al³⁺ into Al(s).
(iv) acts as catalyst.

• a) (i) and (ii)
• b) (iii) and (iv)
• c) (i), (ii) and (iii)
• d) (ii), (iii) and (iv)

Answer: (i) and (ii)

Question: In the extraction of chlorine by electrolysis of brine

• a)

  

• b) a displacement reaction takes place
• c) reduction of Cl^– ion to chlorine gas occurs
• d) oxidation of Cl^– ion to chlorine gas occurs

Answer:

Question:  Brine is electrolysed by using inert electrodes. The reaction at anode is

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: Blister copper is

• a) Cu having 1% impurity
• b) Cu alloy
• c) Impure Cu
• d) Pure Cu

Answer: Cu having 1% impurity

Question: The furnace used to prepare commercial iron is lined with which of the following

• a) Haematite
• b) Magnetite
• c) Ironpyrites
• d) None of these

Answer: Haematite

Question: Which form of the iron contains 4% carbon ?

• a) Pig iron
• b) Cast iron
• c) Wrought iron
• d) None of these

Answer: Pig iron

Question: Which of the following reaction takes place in blast furnace during extraction of copper ?

• a) All of these
• b)

  

• c)

  

• d)

  

Answer: All of these

Question: The main reactions occurring in blast furnace during extraction of iron from haematite are

• a) (i) and (iv)
• b) (i) and (iii)
• c) (ii) and (iv)
• d) (i), (ii) and (iii)

Answer: (i) and (iv)

Question: The process of zone refining is used in the purification of

• a) Si
• b) Ag
• c) Al
• d) Cu

Answer: Si

Question: Van Arkel method of purification of metals involves converting the metal to a

• a) volatile stable compound
• b) volatile unstable compound
• c) non volatile stable compound
• d) None of the above

Answer: volatile stable compound

Question: The method not used in metallurgy to refine the impure metal is

• a) Amalgamation process
• b) Liquation
• c) Mond’s process
• d) Van–Arkel process

Answer: Amalgamation process

Question: Which of the following pairs of metals is purified by van Arkel method ?

• a) Zr and Ti
• b) Ni and Fe
• c) Ga and In
• d) Ag and Au

Answer:  Zr and Ti

Question: The method of zone refining of metals is based on the principle of

• a) greater solubility of the impurities in the molten state than in the solid
• b) greater mobility of the pure metal than that of the impurite
• c) higher melting point of the impurities than that of the pure metal
• d) greater noble character of the solid metal than that of the impurities

Answer: greater solubility of the impurities in the molten state than in the solid 

Question: Method used for obtaining highly pure silicon which is used as a semiconductor material, is

• a) zone refining
• b) electrochemical
• c) oxidation
• d) crystallization

Answer: zone refining

Question: What is anode mud?

• a) Impurities collected at anode in electrolysis during purification of metals
• b) All of these
• c) Metal of anode
• d) Fan of anode

Answer: Impurities collected at anode in electrolysis during purification of metals

Question:  The process of zone refining is used in the purification of

• a) Si
• b) Ag
• c) Al
• d) Cu

Answer: Si

Question: Which of the following statements regarding chromatography is incorrect ?

• a) The mobile phase may be a gas, a liquid or a solid
• b) Component which is more soluble is stationary phase takes longer time to travel
• c) It is based on the principle that different components of mixture gets adsorbed differently on an adsorbent
• d) None of these

Answer: The mobile phase may be a gas, a liquid or a solid

Question: Which of the following metal is used in the manufacture of dye-stuffs and paints ?

• a) Zinc
• b) Magnesium
• c) Copper
• d) Aluminium

Answer: Zinc

Question: Read the following statements

(i) Magnetic separation method is employed when one component either ore or gangue is magnetic in nature.
(ii) Depressant NaCN used in case of ore containing mixture of ZnS and PbS allows ZnS to come with froth and prevents PbS from coming to the froth.
(iii) For concentration powdered bauxite ore is digested with conc.NaOH at 473–523K and 35–36 bar pressure.
Which of the following is the correct code for the statements above ?

• a) TFT
• b) FTF
• c) TTF
• d) FFT

Answer: TFT

Question:

• a) (i) and (iii)
• b) (ii) and (iv)
• c) (i), (ii) and (iii)
• d) (i), (ii) and (iv)

Answer: (i) and (iii)

Question: Which of the following statement(s) is/are correct ?

(i) Cast iron is used in the manufacture of railway sleepers
(ii) Wrought iron is used in the manufacture of anchors, bolts, chains etc.
(iii) Nickel steel is used in making pendulums.

• a) (i), (ii) and (iii)
• b) Only (i)
• c) (i) and (ii)
• d) Only (iii)

Answer: (i), (ii) and (iii)

Question: Read the following statements

(i) The principle that the impurities are more soluble in the melt than in the solid state is used in the manufacture of high purity semiconductors.
(ii) Van Arkel method of refining Zr involves heating of crude metal with Cl₂ to form corresponding halide.
(iii) Mond process for refining of nickel involves formation of metal carbonyls as an intermediate.
Which of the following is the correct code for the statements above ?

• a) TFT
• b) TTT
• c) FFT
• d) FTF

Answer:  TFT

Question:

• a) A– (r), B – (p), C – (s), D – (q)
• b) A– (p), B – (r), C – (s), D – (q)
• c) A– (r), B – (s), C – (p), D – (q)
• d) A– (r), B – (p), C – (q), D – (s)

Answer:  A– (r), B – (p), C – (s), D – (q)

Question:

• a) A – (q), B – (p), C – (s), D – (r)
• b) A – (q), B – (p), C – (r), D – (s)
• c) A – (q), B – (s), C – (p), D – (r)
• d) A – (p), B – (q), C – (s), D – (r)

Answer:  A – (q), B – (p), C – (s), D – (r)

Question:

• a) A – (q), B – (r), C – (s), D – (p)
• b) A – (p), B – (q), C – (r), D – (t)
• c) A – (t), B – (s), C – (r), D – (q)
• d) A – (s), B – (t), C – (r), D – (q)

Answer: A – (q), B – (r), C – (s), D – (p)

Question:

• a) A – (s), B – (r), C – (p), D – (q)
• b) A – (r), B – (s), C – (p), D – (q)
• c) A – (t), B – (s), C – (r), D – (q)
• d) None of these

Answer: A – (s), B – (r), C – (p), D – (q)

Question:

• a) A – (s), B – (q), C – (r), D – (p)
• b) A – (q), B – (r), C – (p), D – (t)
• c) A – (p), B – (q), C – (r), D – (s)
• d) A – (r), B – (s), C – (t), D – (p)

Answer: A – (s), B – (q), C – (r), D – (p)

Question:

• a) A – (s), B – (q), C – (r), D – (p)
• b) A – (r), B – (q), C – (s), D – (p)
• c) A – (s), B – (p), C – (r), D – (q)
• d) A – (r), B – (p), C – (s), D – (q)

Answer: A – (s), B – (q), C – (r), D – (p)

Question:

• a) A – (s), B – (r), C – (t), D – (q), E – (p)
• b) A – (s), B – (t), C – (r), D – (q), E – (p)
• c) A – (s), B – (r), C – (p), D – (q), E – (t)
• d) A – (r), B – (s), C – (t), D – (q), E – (p)

Answer: A – (s), B – (r), C – (t), D – (q), E – (p)

Question:

• a) A – (q), B – (r), C – (p), D – (s)
• b) A – (r), B – (q), C – (p), D – (s)
• c) A – (q), B – (p), C – (r), D – (s)
• d) A – (q), B – (r), C – (s), D – (p)

Answer: A – (q), B – (r), C – (p), D – (s)

Question:

Assertion : Levigation is used for the separation of oxide ores from impurities.
Reason : Ore particles are removed by washing in a current of water.

• a) Assertion is correct, reason is incorrect
• b) Assertion is incorrect, reason is correct
• c) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
• d) Assertion is correct, reason is correct; reason is a correct explanation for assertion.

Answer: Assertion is correct, reason is incorrect

Question:

Assertion : Zinc can be used while copper cannot be used in the recovery of Ag from the complex [Ag(CN)₂]^–.
Reason : Zinc is a powerful reducing agent than copper.

• a) Assertion is correct, reason is correct; reason is a correct explanation for assertion.
• b) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
• c) Assertion is correct, reason is incorrect
• d) Assertion is incorrect, reason is correct

Answer: Assertion is correct, reason is correct; reason is a correct explanation for assertion.

Question:

Assertion : Leaching is a process of reduction.
Reason : Leaching involves treatment of the ore with a suitable reagent so as to make it soluble while impurities remains insoluble.

• a) Assertion is incorrect, reason is correct
• b) Assertion is correct, reason is incorrect
• c) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
• d) Assertion is correct, reason is correct; reason is a correct explanation for assertion

Answer: Assertion is incorrect, reason is correct

Question:

Assertion : Coke and flux are used in smelting.
Reason : The phenomenon in which ore is mixed with suitable flux and coke is heated to fusion is known as smelting.

• a) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
• b) Assertion is correct, reason is incorrect
• c) Assertion is incorrect, reason is correct
• d) Assertion is correct, reason is correct; reason is a correct explanation for assertion

Answer: Assertion is correct, reason is correct; reason is not a correct explanation for assertion

Question:

Assertion : Lead, tin and bismuth are purified by liquation method.
Reason : Lead, tin and bismuth have low m.p. as compared to impurities.

• a) Assertion is correct, reason is correct; reason is a correct explanation for assertion
• b) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
• c) Assertion is correct, reason is incorrect
• d) Assertion is incorrect, reason is correct

Answer: Assertion is correct, reason is correct; reason is a correct explanation for assertion

Question: Which of the following metal is correctly matched with its ore?

• a)

  

   

• b)

  

   

• c)

  

   

• d) None of these

Answer:

Question:

Assertion : Copper obtained after bessemerization is known as blister copper.
Reason : Blisters are produced on the surface of the metal due to escaping of dissolved SO₂

• a) Assertion is correct, reason is correct; reason is a correct explanation for assertion
• b) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
• c) Assertion is correct, reason is incorrect
• d) Assertion is incorrect, reason is correct

Answer: Assertion is correct, reason is correct; reason is a correct explanation for assertion

Question: Copper can be extracted from

• a) Malachite
• b) Kupfernical
• c) Dolomite
• d) Galena

Answer: Malachite

Question: Which ore contains both iron and copper?

• a) Chalcopyrite
• b) Cuprite
• c) Chalcocite
• d) Malachite

Answer: Chalcopyrite

Question: Sulfide ores are common for the metals

• a) Ag, Cu and Pb
• b) Ag, Cu and Sn
• c) Ag, Mg and Pb
• d) Al, Cu and Pb

Answer: Ag, Cu and Pb

Question: Which one of the following does not occur as sulphide ore?

• a) Cr
• b) Fe
• c) Zn
• d) Ag

Answer: Cr

Question: Pyrolusite is a/an

• a) oxide ore
• b) carbide ore
• c) sulphide ore
• d) Not an ore

Answer: oxide ore

Question: Sulphide ores of metals are usually concentrated by froth flotation process. Which one of the following sulphide ores offer an exception and is concentrated by chemical leaching?

• a) Argentite
• b) Copper pyrite
• c) Galena
• d) Sphalerite

Answer: Argentite

Question: Which of the following statements is correct

• a) Fluxes are carefully chosen to combine with the gangue present in the ore to produce easily fusible slag to carry away the impurities
• b) Gangues are carefully chosen to combine with the flux present in the ore to produce easily fusible slag to carry away the impurities
• c) Slags are carefully chosen to combine with the flux present in the ore to produce easily fusible gangue to carry away the impurities
• d) Gangues are carefully chosen to combine with the slag present in the ore to produce easily fusible flux to carry away the impurities

Answer: Fluxes are carefully chosen to combine with the gangue present in the ore to produce easily fusible slag to carry away the impurities

Question: Carbon and CO gas are used to reduce which of the following pairs of metal oxides for extraction of metals ?

• a) FeO, ZnO
• b) SnO, ZnO
• c) FeO, SnO
• d) None of these

Answer: FeO, ZnO

Question: In the cyanide extraction process of silver from argentite ore, the oxidising and reducing agents used are

• a) O₂ and Zn dust respectively
• b) O₂ and CO respectively
• c) HNO₃ and CO respectively
• d) HNO₃ and Zn dust respectively

Answer: O₂ and Zn dust respectively

Question:

• a) zinc oxide can be reduced by graphite
• b) zinc can be oxidised by carbon monoxide
• c) carbon monoxide can be reduced by zinc
• d) both statements (a) and (b) are true

Answer: zinc oxide can be reduced by graphite

Question: Which of the following statements, about the advantage of roasting of sulphide ore before reduction is not true?

• a) Carbon and hydrogen are suitable reducing agents for reduction of metal sulphides.
• b) Roastin of the sulphide to the oxide is thermodynamically feasible
• c)

  

• d)

  

Answer: Carbon and hydrogen are suitable reducing agents for reduction of metal sulphides.

Question: Which of the following statement is not correct about Ellingham diagram?

• a) It express the kinetics of the reduction process
• b) a coupling reaction can be well expressed by this diagram
• c)

  

• d) None of these

Answer: It express the kinetics of the reduction process

Question:

• a)

  

• b) x < y
• c) x > y
• d) 2x = y

Answer:

Question:

• a) –287 kJ mol–1
• b) +287 kJ mol–1
• c) – 574 kJ mol–1
• d) + 574 kJ mol–1

Answer: –287 kJ mol–1

Question: Before introducing FeO in blast furnace , it is converted to Fe₂O₃ by roasting so that

• a) it may not be removed as slag with silica
• b) it may not evaporate in the furnace
• c) presence of it may increase the m.pt. of charge
• d) None of these

Answer: it may not be removed as slag with silica

Question: The temperature in °C at which Fe₂O₃ is finally reduced to Fe in the blast furnace is

• a) 993
• b) 897
• c) 797
• d) 1597

Answer: 993

Question: When copper ore is mixed with silica, in a reverberatory furnace copper matte is produced. The copper matte contains________.

• a) sulphides of copper (I) and iron (II)
• b) sulphides of copper (I) and iron (III)
• c) sulphides of copper (II) and iron (III)
• d) sulphides of copper (II) and iron (II)

Answer: sulphides of copper (I) and iron (II)

Question: In the metallurgy of aluminium

• a) graphide anode is oxidised to carbon monoxide and carbon dioxide
• b) oxidation state of oxygen changes in the reaction at anode.
• c) oxidation state of oxygen changes in the overall reaction involved in the process
• d) Al³⁺ is oxidised to Al (s).

Answer: graphide anode is oxidised to carbon monoxide and carbon dioxide

Question:

• a) (ii) and (iii)
• b) (iii) and (iv)
• c) (i) and (ii)
• d) (i) and (iv)

Answer: (ii) and (iii)

Question:

• a) Self reduction
• b) Purification
• c) Roasting
• d) Refining

Answer: Self reduction

Question: Which of the following statements regarding metallurgy of iron is incorrect ?

• a) The iron obtained from blast furnace is cast iron with 3% carbon
• b)

  

• c)

  

• d) None of these

Answer: The iron obtained from blast furnace is cast iron with 3% carbon

Question: Extraction of which of the following is based on oxidation

• a) Non-metals
• b) Moderately reactive metals
• c) Highly reactive metals
• d) None of these

Answer: Non-metals

Question:

• a) (i) and (ii)
• b) (iii) and (iv)
• c) (i), (ii) and (iii)
• d) (iv) only

Answer: (i) and (ii)

Question: In Hall-Heroult process how much carbon anode is burnt away to produce each 1kg of aluminium

• a) 0.5 kg
• b) 0.1 kg
• c) 0.3 kg
• d) 1 kg

Answer: 0.5 kg

Question: In electro-refining of metal the impure metal is used to make the anode and a strip of pure metal as the cathode, during the electrolysis of an aqueous solution of a complex metal salt. This method cannot be used for refining of

• a) Sodium
• b) Copper
• c) Silver
• d) Aluminium

Answer: Sodium

Question: During the process of electrolytic refining of copper, some metals present as impurity settle as ‘anode mud’. These are

• a) Ag and Au
• b) Sn and Ag
• c) Fe and Ni
• d) Pb and Zn

Answer: Ag and Au