JEE Main Previous year questions (2022-23): General Principles & Processes of Isolation of Elements PDF Download

Q.1. The metal which is extracted by oxidation and subsequent reduction from its ore is:     (JEE Main 2023)
(a) Ag
(b) Fe
(c) Cu
(d) Al

Ans. a

Q.2. Match List I with List II

Choose the correct answer from the options given below:      (JEE Main 2023)
(a) A-IV, B-II, C-I, D-III
(b) A-I, B-III, C-II, D-IV
(c) A-III, B-IV, C-I, D-II
(d) A-I, B-IV, C-II, D-III

Ans. a
Reverberatory furnance → Cr
Electrolysis cell → Ar
Blast furnance → Pig iron
Zone refining furnance  → silicon

Q.3. The electrochemical extraction of aluminum from bauxite ore involves     (JEE Advanced 2022)
(a) The reaction of Al₂O₃ with coke (C) at a temperature > 2500^oC
(b) The neutralization of aluminate solution by passing CO₂ gas to precipitate hydrated alumina (Al₂O₃·3H₂O)
(c) The dissolution of Al₂O₃ in hot aqueous NaOH
(d) The electrolysis of Al₂O₃ mixed with Na₃AIF₆ to give Al and CO₂

Ans. b, c and d

Q.4. The correct option(s) related to the extraction of iron from its ore in the blast furnace operating in the temperature range 900 – 1500 K is(are)   (JEE Advanced 2022)
(a) Limestone is used to remove silicate impurity. 
(b) Pig iron obtained from blast furnace contains about 4% carbon. 
(c) Coke (C) converts CO₂ to CO. 
(d) Exhaust gases consist of NO₂ and CO.

Ans. a, b and c

Q.5. In metallurgy the term "gangue" is used for    (JEE Main 2022)
(a) Contamination of undesired earthy materials
(b) Contamination of metals, other than desired metal
(c) Minerals which are naturally occurring in pure form
(d) Magnetic impurities in an ore

Ans. a
Earthy and undesired materials present in the ore other then the desired metal is known as gangue.

Q.6. Which of the reaction is suitable for concentrating ore by leaching process?     (JEE Main 2022)
(a) 2Cu₂S+30₂ → 2Cu₂O + 2SO₂
(b) Fe₃O₄, + CO → 3FeO + CO₂
(c) Al₂O₃ + 2NaOH + 3H₂O → 2Na[Al(OH)₄]
(d) Al₂O₃ + 6Mg → 6MgO + 4AI

Ans. c
Leaching involves the treatment of ore with a suitable reagent so as it make it soluble while impurities remain insoluble.

Q.7. Match List - I with List - II.     (JEE Main 2022)

Choose the correct answer from the options given below:
(a) (A) - (IV), (B) - (III), (C) - (I), (D) - (II) 
(b) (A) - (III), (B) - (I), (C) - (IV), (D) - (II) 
(c) (A) - (III), (B) - (IV), (C) - (II), (D) - (I) 
(d) (A) - (III), (B) - (IV), (C) - (I), (D) - (II) 

Ans. d
(A) Chloroform + Aniline → (III) Distillation 
(B) Benzoic acid + Napthalene → (IV) Crystallisation 
(C) Water + Aniline → (I) Steam distillation 
(D) Napthalene + Sodium chloride → (II) Sublimation

Q.8. Given below are two statements:   (JEE Main 2022)
Statement I : The non bio-degradable fly ash and slag from steel industry can be used by cement industry.
Statement II : The fuel obtained from plastic waste is lead free.
In the light of the above statements, choose the most appropriate answer from the options given below:
(a) Both Statement I and Statement II are correct
(b) Both Statement I and Statement II are incorrect
(c) Statement I is correct but Statement II is incorrect
(d) Statement I is incorrect but Statement II is correct

Ans. a
Both Statement are correct.
- Fuel obtained from plastic waste has high octane rating. It contain no lead and is known as "green fuel".
- The non bio-degradable fly ash and slag from steel industry can be used by cement industry.

Q.9. Which of the following methods are not used to refine any metal?   (JEE Main 2022)
A. Liquation
B. Calcination
C. Electrolysis
D. Leaching
E. Distillation
Choose the correct answer from the options given below:
(a) B and D only
(b) A, B, D and E only
(c) B, D and E only
(d) A, C and E only

Ans. a
Leaching and calcination are the processes which are involved in the extraction of the metals. Liquation, Electrolytic refining, Distillation are used in the refining or purification of metal. 

Q.10. The metal that is not extracted from its sulfide ore is   (JEE Main 2022)
(a) Aluminium
(b) Iron
(c) Lead
(d) Zinc 

Ans. a
Aluminium is not extracted from sulphide ore. It is usually extracted from bauxite ore, leaching of bauxite ore is done followed by electrolytic reduction.

Q.11. Given below are two statements.   (JEE Main 2022)
Statement I : Pig iron is obtained by heating cast iron with scrap iron.
Statement II : Pig iron has a relatively lower carbon content than that of cast iron.
In the light of the above statements, choose the correct answer from the options given below.
(a) Both Statement I and Statement II are correct.
(b) Both Statement I and Statement II are not correct.
(c) Statement I is correct but Statement II is not correct.
(d) Statement I is not correct but Statement II is correct.

Ans. b
Cast iron is made by melting pig iron with scrap iron and coke using hot air blast.
Hence Statement-I is incorrect
But Pig iron has relatively more carbon content
Hence statement-II is incorrect

Q.12. The compound(s) that is (are) removed as slag during the extraction of copper is:
(A) CaO
(B) FeO
(C) Al₂O₃
(D) ZnO
(E) NiO
Choose the correct answer from the options given below:    (JEE Main 2022)
(a) (C), (D) only
(b) (A), (B), (E) only
(c) (A), (B) only
(d) (B) only 

Ans. d

Q.13. Match List - I with List - II:      (JEE Main 2022)

Choose the most appropriate answer from the options given below:
(a) (A)-(IV), (B)-(III), (C)-(II), (D)-(I)
(b) (A)-(IV), (B)-(I), (C)-(II), (D)-(III)
(c) (A)-(II), (B)-(III), (C)-(I), (D)-(IV)
(d) (A)-(III), (B)-(IV), (C)-(II), (D)-(I) 

Ans. a

Hence, the most appropriate option is (A). 

Q.14. Which of the following chemical reactions represents Hall-Heroult Process? (JEE Main 2022)
(a) Cr₂O₃ + 2Al → Al₂O₃ + 2Cr
(b) 2Al₂O₃ + 3C → 4Al + 3CO₂
(c) FeO + CO → Fe + CO₂
(d) 2[Au(CN)₂]_(aq) + Zn(s) → Zn(s) →2Au(s) + [Zn(CN₄)]^2-

Ans. b
Hall-Herault process is used for the extraction of aluminium by electrolysis molten Al₂O_{3
2Al2O3 + 3C → 4Al + 3CO2}

Q.15. Using very little soap while washing clothes, does not serve the purpose of cleaning of clothes, because:     (JEE Main 2022)
(a) soap particles remain floating in water as ions
(b) the hydrophobic part of soap is not able to take away grease
(c) the micelles are not formed due to concentration of soap, below its CMC value
(d) colloidal structure of soap in water is completely disturbed

Ans. c
The little amount of using soap while washing clothes, does not serve the purpose of cleaning of clothes because the micelles are not formed due to the low concentration of soap as it is below CMC.

Q.16. Leaching of gold with dilute aqueous solution of NaCN in presence of oxygen gives complex [A], which on reaction with zinc forms the elemental gold and another complex [B]. [A] and [B], respectively are:     (JEE Main 2022)
(a) [Au(CN)₄]^- and [Zn(CN₂),(OH)₂]^2-
(b) [Au(CN₂)]^- and [Zn(OH)₄]^2-
(c) [Au(CN₂)]^- and [Zn(CN)₄]^2-
(d) [Au(CN)₄]^2- and [Zn(CN)₆]^4-

Ans. c

Q.17. Given below are two statements.     (JEE Main 2022)
Statement I : During electrolytic refining, blister copper deposits precious metals.
Statement II : In the process of obtaining pure copper by electrolysis method, copper blister is used to make the anode.
In the light of the above statements, choose the correct from the options given below.
(a) Both Statement I and Statement II are true
(b) Both Statement I and Statement II are false
(c) Statement I is true but Statement II is false
(d) Statement I is false but Statement II is true

Ans. a
Copper is refined using an electrolytic method. Anodes are of impure copper and pure copper strips are taken as cathode. Impurities from the blister copper deposit as anode mud which contains antimony, selenium, tellurium, silver, gold and platinum. Hence both statements are true

Q.18. The role of depressants in 'Froth Flotation method' is to     (JEE Main 2022)
(a) selectively prevent one component of the ore from coming to the froth.
(b) reduce the consumption of oil for froth formation.
(c) stabilize the froth.
(d) enhance non-wettability of the mineral particles. 

Ans. a
Depressant prevent one component from coming to the froth. For eg., in Galena ore, the depressant (NaCN) prevents impurity (ZnS) from coming to the froth.

Q.19. Given below are two statements:     (JEE Main 2022)
Statement I: According to Ellingham diagram, any metal oxide with higher ΔG^∘ is more stable than the one with lower ΔG^∘.
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:
(a) Both Statement I and Statement II are correct.
(b) Both Statement I and Statement II are incorrect.
(c) Statement I is correct but Statement II is incorrect.
(d) Statement I is incorrect but Statement II is correct.

 Ans. d
Ellingham diagram is plot of ΔG vs T. The criterion for the feasibility of a thermal reduction is that at a given temperature Gibbs energy change of a reaction must be negative. The change in Gibbs energy, ΔG for any process at any specified temperature is given by the equation
ΔG = ΔH - TΔS 
where ΔH = enthalpy change and ΔS = entropy change 
According to the ellingham diagram, any metal oxide with higher ΔG° has a tendency of getting reduced by the metal whose metal oxide has lower value of ΔG°. 

Q.20. Which of the following is structure of a separating funnel?     (JEE Main 2022)
(a)

(b)
(c)
(d)

Ans. a

Q.21. Match List-I with List-II     (JEE Main 2022)

Choose the correct answer from the options given below :
(a) (A) - (IV), (B) - (III), (C) - (II), (D) - (I)
(b) (A) - (IV), (B) - (II), (C) - (I), (D) - (III)
(c) (A) - (III), (B) - (II), (C) - (I), (D) - (IV)
(d) (A) - (II), (B) - (IV), (C) - (III), (D) - (I)

Ans. b
Gold is concentrated by cyanidation
Leaching of alumina is done by NaOH
Froth stabiliser is aniline
Blister copper has condensed SO₂ on the surface 

Q.22. Statement I : Leaching of gold with cyanide ion in absence of air / O₂ leads to cyano complex of Au(III).     (JEE Main 2022)
Statement II : Zinc is oxidized during the displacement reaction carried out for gold extraction.
In the light of the above statements, choose the correct answer from the options given below.

(a) Both Statement I and Statement II are correct.
(b) Both Statement I and Statement II are incorrect.
(c) Statement I is correct but Statement II is incorrect.
(d) Statement I is incorrect but Statement II is correct.

Ans. d
Leaching of gold with cyanide ion is done in presence of air/O₂ leading to cyano complex [Au(CN)₂]^– where Au is in +1 oxidation state. 


Zinc is oxidised from (0) to +2 oxidation state during displacement reaction carried out for gold extraction. 

Q.23. Given are two statements one is labelled as Assertion A and other is labelled as Reason R.     (JEE Main 2022)
Assertion A: Magnesium can reduce Al₂O₃ at a temperature below 1350^∘C, while above 1350∘C, while above 1350^∘C aluminium can reduce MgO.
Reason R: The melting and boiling points of magnesium are lower than those of aluminium.

In light of the above statements, choose most appropriate answer from the options given below:
(a) Both A and R are correct, and R is correct explanation of A.
(b) Both A and R are correct, but R is NOT the correct explanation of A.
(c) A is correct R is not correct.
(d) A is not correct, R is correct. 

Ans. b
Magnesium can reduce Al₂O₃ at a temperature below 1350°C while above 1350°C aluminium can reduce MgO because below 1350°C ΔG of MgO (formation) is more negative and above 1350°C ΔG of Al₂O₃ (formation) is more negative.
The melting and boiling point of magnesium are lower than those of aluminium but it is not the correct reason. 

Q.24. In the metallurgical extraction of copper, following reaction is used:     (JEE Main 2022)
FeO + SiO₂ → FeSiO₃
FeO and FeSiO₃ respectively are.
(a) Gangue and flux
(b) Flux and slag
(c) Slag and flux
(d) Gangue and slag

Ans. d
FeO + SiO₂ → FeSiO₃
FeO = Gangue and FeSiO₃ = Slag 

Q.25. Match List I with List II.      (JEE Main 2022)

Choose the correct answer from the options given below :
(a) A-I, B-II, C-III, D-IV
(b) A-III, B-IV, C-II, D-I
(c) A-IV, B-III, C-I, D-II
(d) A-I, B-II, C-IV, D-III

Ans. a
Siderite → FeCO₃

Malachite → CuCO₃. Cu(OH)₂

Sphalerite → ZnS

Calamine → ZnCO₃

Note : ( Remember all those ores names. Any one of those can be asked in the exam.)

Oxides Ores :

(1) ZnO - Zincite

(2) Fe₂O₃ - Haematite

(3) Fe₃O₄ - Magnetite (FeO + Fe₂O₃ mixture)

(4) Fe₂O₃ . 3H₂O - Limonite

(5) MnO₂ - Pyrolusite

(6) Cu₂O - Cuprite or Ruby Copper

(7) TiO₂ - Rutile

(8) FeCr₂O₄ - Chromite (FeO + Cr₂O₃)

(9) FeTiO₃ - Illmenite (FeO + TiO₂)

(10) Na₂B₄O₇ . 10H₂O - Borax or Tincal

(11) U₃O₈ - Pitch Blende

(12) SnO₂ - Tin Stone or Cassiterite

(13) Ca₂B₆O₁₁ . 5H₂O - Colemanite (2 Cao + 3 B₂O₃)

(14) Al₂O₃ . 2H₂O - Bauxite

(15) Al₂O₃ . H₂O - Diaspore

(16) Al₂O₃ - Corundum

Sulphides Ores :

(1) ZnS - Zinc Blende or Sphalerite

(2) PbS - Galena

(3) Ag₂S - Argentite or Silver Glance

(4) HgS - Cinnabar

(5) Cu₂S - Chalcocite or Copper glance

(6) CuFeS₂ - Copper pyrites or Chalco pyrites (Cu₂S + Fe₂S₃ mixture)

(7) FeS₂ - Iron pyrites or Fool's Gold

(8) 3Ag₂S . Sb₂S₂ - Pyrargyrite or ruby silver

Halides Ores :

(1) NaCl - Rock Salt

(2) KCl - Sylvine

(3) Na₃AlF₆ - Cryolite [3NaF + AlF₆]

(4) CaF₂ - Fluorspar

(5) KCl . MgCl₂ . 6H₂O - Carnalite

(6) AgCl - Horn Silver

Carbonates Ores :

(1) CaCO₃ - Limestone

(2) MgCO₃ - Magnesite

(3) CaCO₃ . MgCO₃ - Dolomite

(4) ZnCO₃ - Calamine

(5) PbCO₃ - Cerrusite

(6) FeCO₃ - Siderite

(7) CuCO₃ . Cu(OH)₂ or Cu₂CO₃(OH)₂ - Malachite or Basic Copper Carbonates

(8) 2 CuCO₃ . Cu(OH)₂ - Azurite

Sulphates Ores :

(1) CuSO₄ . 2H₂O - Gypsum

(2) MgSO₄ . 7H₂O - Epson Salt

(3) Na₂SO₄ . 10 H₂O - Glauber's Salt

(4) PbSO₄ - Anglesite

(5) ZnSO₄ . 7H₂O - White Vitriol

(6) FeSO₄ . 7H₂O - Green Vitriol

(7) CuSO₄ . 5H₂O - Blue Vitriol or Chalcanthite

Nitrate Ores :

(1) KNO₃ - Indian Saltpetre

(2) NaNO₃ - Chile Saltpetre

Arsenides Ores :

(1) NiAs - Kupfernickel

(2) NiAsS - Nickel glance

Q.26. In isolation of which one of the following metals from their ores, the use of cyanide salt is not commonly involved?     (JEE Main 2022)
(a) Zinc
(b) Gold
(c) Silver
(d) Copper

Ans. d
In the extraction of Silver and Gold, NaCN is used to leach the metal. 

In case of ore containing ZnS and PbS, the depressant used is NaCN. 

Q.27. Among the following the number of curves not in accordance with Freundlich adsorption isotherm is ________.     (JEE Main 2022)

Ans. 3

Q.28. Among the following ores Bauxite, Siderite, Cuprite, Calamine, Haematite, Kaolinite, Malachite, Magnetite, Sphalerite, Limonite, Cryolite, the number of principal ores if iron is _____________.     (JEE Main 2022)

Ans. 4
The principal ores of iron are : Siderite, Haematite, Magnetite, Limonite.

Q.29. Blister copper is produced by reaction of copper oxide with copper sulphide.
2Cu₂O + Cu₂S → 6Cu + SO₂
When 2.86 × 10³ g of Cu₂O and 4.77 × 10³ g of Cu₂S are used for reaction, the mass of copper produced is _____________ g. (nearest integer)
(Atomic mass of Cu = 63.5 a.m. u, S = 32.0 a.m. u, O = 16.0 a.m. u)     (JEE Main 2022)

Ans. 3810
moles of 
moles of 
Cu₂O is limiting reagent 

Mass of copper  = 60 × 63.5 = 3810g

Q.30. (a) Baryte, (b) Galena, (c) Zinc blende and (d) Copper pyrites. How many of these minerals are sulphide based?     (JEE Main 2022)

Ans. 3
Baryte: BaSO₄
Galena: PbS
Zinc blende: ZnS
Copper pyrites: CuFeS₂
Of the given minerals, only 3 are sulphide based. 

Q.31. A mixture of two salts is used to prepare a solution S, which gives the following results:
The correct option(s) for the salt mixture is(are)           (JEE Advanced 2021)
(a) Pb(NO₃)₂ and Zn(NO₃)₂
(b) Pb(NO3)₂ and Bi(NO₃)3
(c) AgNO₃ and Bi(NO₃)3
(d) Pb(NO₃)₂and Hg(NO₃)₂

Ans. a, b

Q.32. The correct statement(s) related to the metal extraction processes is (are):           (JEE Advanced 2021)
(a) A mixture of PbS and PbO undergoes self-reduction to produce Pb and SO₂ 
(b) In the extraction process of copper from copper pyrites, silica is added to produce copper silicate.
(c) Partial oxidation of sulphide ore of copper by roasting, followed by self-reduction produces blister copper.
(d) In cyanide process, zinc powder is utilized to precipitate gold from Na[Au(CN)₂]

Ans. a, c, d
Statements (a), (c) and (d) are correct, whereas statement (b) is incorrect. All statements are explained as follows :
(a) A mixture PbO and PbS reacts as follows:

This reaction is known as self-reduction.
(b) Silica is added to remove impurities of Fe in the form of slag, FeSiO₃ .
(c) CuFeS₂ are in partially oxidised first by roasting and then self-reduction of Cu takes place to produce blister copper.
(d) Zn powder reacts with Na[Au(CN)₂ ] to form gold. This process is called cyanide process.
2Zn + 4Na[Au(CN)₂] → 2Na₂[Zn(CN)₄]+ 4Au

Q.33. Calamine and Malachite, respectively, are the ores of:           (JEE Main 2021)
(a) Nickel and Aluminium
(b) Zinc and Copper
(c) Copper and Iron
(d) Aluminium and Zinc

Ans. b
Calamine ⇒ ZnCO₃
Malachite ⇒ Cu(OH)₂ . CuCO₃
Note : ( Remember all those ores names. Any one of those can be asked in the exam.)
Oxides Ores :
(1) ZnO - Zincite
(2) Fe₂O₃ - Haematite
(3) Fe₃O₄ - Magnetite (FeO + Fe₂O₃ mixture)
(4) Fe₂O₃ . 3H₂O - Limonite
(5) MnO₂ - Pyrolusite
(6) Cu₂O - Cuprite or Ruby Copper
(7) TiO₂ - Rutile
(8) FeCr₂O₄ - Chromite (FeO + Cr₂O₃)
(9) FeTiO₃ - Illmenite (FeO + TiO₂)
(10) Na₂B₄O₇ . 10H₂O - Borax or Tincal
(11) U₃O₈ - Pitch Blende
(12) SnO₂ - Tin Stone or Cassiterite
(13) Ca₂B₆O₁₁ . 5H₂O - Colemanite (2 Cao + 3 B₂O₃)
(14) Al₂O₃ . 2H₂O - Bauxite
(15) Al₂O₃ . H₂O - Diaspore
(16) Al₂O₃ - Corundum
Sulphides Ores :
(1) ZnS - Zinc Blende or Sphalerite
(2) PbS - Galena
(3) Ag₂S - Argentite or Silver Glance
(4) HgS - Cinnabar
(5) Cu₂S - Chalcocite or Copper glance
(6) CuFeS₂ - Copper pyrites or Chalco pyrites (Cu₂S + Fe₂S₃ mixture)
(7) FeS₂ - Iron pyrites or Fool's Gold
(8) 3Ag₂S . Sb₂S₂ - Pyrargyrite or ruby silver
Halides Ores :
(1) NaCl - Rock Salt
(2) KCl - Sylvine
(3) Na₃AlF₆ - Cryolite [3NaF + AlF₆]
(4) CaF₂ - Fluorspar
(5) KCl . MgCl₂ . 6H₂O - Carnalite
(6) AgCl - Horn Silver
Carbonates Ores :
(1) CaCO₃ - Limestone
(2) MgCO₃ - Magnesite
(3) CaCO₃ . MgCO₃ - Dolomite
(4) ZnCO₃ - Calamine
(5) PbCO₃ - Cerrusite
(6) FeCO₃ - Siderite
(7) CuCO₃ . Cu(OH)₂ or Cu₂CO₃(OH)₂ - Malachite or Basic Copper Carbonates
(8) 2 CuCO₃ . Cu(OH)₂ - Azurite
Sulphates Ores :
(1) CuSO₄ . 2H₂O - Gypsum
(2) MgSO₄ . 7H₂O - Epson Salt
(3) Na₂SO₄ . 10 H₂O - Glauber's Salt
(4) PbSO₄ - Anglesite
(5) ZnSO₄ . 7H₂O - White Vitriol
(6) FeSO₄ . 7H₂O - Green Vitriol
(7) CuSO₄ . 5H₂O - Blue Vitriol or Chalcanthite
Nitrate Ores :
(1) KNO₃ - Indian Saltpetre
(2) NaNO₃ - Chile Saltpetre
Arsenides Ores :
(1) NiAs - Kupfernickel
(2) NiAsS - Nickel glance 

Q.34. Given below are two statements:            (JEE Main 2021)
Statement I : The process of producing syn-gas is called gasification of coal.
Statement II : The composition of syn-gas is CO + CO₂ + H₂ (1 : 1 : 1)
In the light of the above statements, choose the most appropriate answer from the options given below:
(a) Statement I is false but Statement II is true
(b) Statement I is true but Statement II is false
(c) Both Statement I and Statement II are false
(d) Both Statement I and Statement II are true

Ans. b
The process of producing syn-gas from coal is called gasification of coal.
Syn-gas having composition of CO & H₂ in 1 : 1 

Q.35. Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : Aluminium is extracted from bauxite by the electrolysis of molten mixture of Al₂O₃ with cryolite.
Reason (R) : The oxidation state of Al in cryolite is +3.
In the light of the above statements, choose the most appropriate answer from the options given below:             (JEE Main 2021)
(a) (A) is true but (R) is false.
(b) (A) is false but (R) is true.
(c) Both (A) and (R) are correct and (R) is the correct explanation of (A)
(d) Both (A) and (R) are correct but (R) is not the correct explanation of (A)

Ans. d
(A) Aluminium is reactive metal so Aluminium is extracted by electrolysis of Alumina with molten mixture of Cryolite
(B) Cryolite, Na₃AlF₆
Here, Al is in +3 O.S.
So, answer is (d).

Q.36. Match List-I with List-II:             (JEE Main 2021)

Choose the most appropriate answer from the options given below :
(a) (a)-(iii), (b)-(iv), (c)-(ii), (d)-(i)
(b) (a)-(iii), (b)-(iv), (c)-(i), (d)-(ii)
(c) (a)-(iv), (b)-(iii), (c)-(i), (d)-(ii)
(d) (a)-(iii), (b)-(ii), (c)-(iv), (d)-(i)

Ans. a
(Name of ore/mineral)
(a) Calamine - ZnCO₃
(b) Malachite - CuCO₃ . Cu(OH)₂
(c) Siderite - FeCO₃
(d) Sphalerite - ZnS
Note : ( Remember all those ores names. Any one of those can be asked in the exam.)
Oxides Ores :
(1) ZnO - Zincite
(2) Fe₂O₃ - Haematite
(3) Fe₃O₄ - Magnetite (FeO + Fe₂O₃ mixture)
(4) Fe₂O₃ . 3H₂O - Limonite
(5) MnO₂ - Pyrolusite
(6) Cu₂O - Cuprite or Ruby Copper
(7) TiO₂ - Rutile
(8) FeCr₂O₄ - Chromite (FeO + Cr₂O₃)
(9) FeTiO₃ - Illmenite (FeO + TiO₂)
(10) Na₂B₄O₇ . 10H₂O - Borax or Tincal
(11) U₃O₈ - Pitch Blende
(12) SnO₂ - Tin Stone or Cassiterite
(13) Ca₂B₆O₁₁ . 5H₂O - Colemanite (2 Cao + 3 B₂O₃)
(14) Al₂O₃ . 2H₂O - Bauxite
(15) Al₂O₃ . H₂O - Diaspore
(16) Al₂O₃ - Corundum
Sulphides Ores :
(1) ZnS - Zinc Blende or Sphalerite
(2) PbS - Galena
(3) Ag₂S - Argentite or Silver Glance
(4) HgS - Cinnabar
(5) Cu₂S - Chalcocite or Copper glance
(6) CuFeS₂ - Copper pyrites or Chalco pyrites (Cu₂S + Fe₂S₃ mixture)
(7) FeS₂ - Iron pyrites or Fool's Gold
(8) 3Ag₂S . Sb₂S₂ - Pyrargyrite or ruby silver
Halides Ores :
(1) NaCl - Rock Salt
(2) KCl - Sylvine
(3) Na₃AlF₆ - Cryolite [3NaF + AlF₆]
(4) CaF₂ - Fluorspar
(5) KCl . MgCl₂ . 6H₂O - Carnalite
(6) AgCl - Horn Silver
Carbonates Ores :
(1) CaCO₃ - Limestone
(2) MgCO₃ - Magnesite
(3) CaCO₃ . MgCO₃ - Dolomite
(4) ZnCO₃ - Calamine
(5) PbCO₃ - Cerrusite
(6) FeCO₃ - Siderite
(7) CuCO₃ . Cu(OH)₂ or Cu₂CO₃(OH)₂ - Malachite or Basic Copper Carbonates
(8) 2 CuCO₃ . Cu(OH)₂ - Azurite
Sulphates Ores :
(1) CuSO₄ . 2H₂O - Gypsum
(2) MgSO₄ . 7H₂O - Epson Salt
(3) Na₂SO₄ . 10 H₂O - Glauber's Salt
(4) PbSO₄ - Anglesite
(5) ZnSO₄ . 7H₂O - White Vitriol
(6) FeSO₄ . 7H₂O - Green Vitriol
(7) CuSO₄ . 5H₂O - Blue Vitriol or Chalcanthite
Nitrate Ores :
(1) KNO₃ - Indian Saltpetre
(2) NaNO₃ - Chile Saltpetre
Arsenides Ores :
(1) NiAs - Kupfernickel
(2) NiAsS - Nickel glance

Q.37. Which refining process is generally used in the purification of low melting metals?             (JEE Main 2021)
(a) Chromatographic method
(b) Liquation
(c) Electrolysis
(d) Zone refining

Ans. b
Liquation method is used to purify those impure metals which has lower melting point than the melting point of impurities associated.
∴ This method is used for metal having low melting point.

Q.38. Given below are two statements:             (JEE Main 2021)
Statement I : Sphalerite is a sulphide or of zinc and copper glance is a sulphide ore of copper.
Statement II : It is possible to separate two sulphide ores by adjusting proportion of oil to water or by using 'depressants' in a forth flotation method.
Choose the most appropriate answer from the options given below:
(a) Statement I is true but Statement II is false.
(b) Both Statement I and Statement II are true.
(c) Statement I is false but Statement II is true.
(d) Both Statement I and Statement II are false.

Ans. b
sphalerite-ZnS, copper glance - Cu₂S two sulphide ores can be separated by adjusting proportions of oil to water or by using 'Depressants'.

Q.39. Given below are two statements:             (JEE Main 2021)
Statement I: The choice of reducing agents for metals extraction can be made by using Ellingham diagram, a plot of ΔG vs temperature. 
Statement II: The value of ΔS increases from left to right in Ellingham diagram. 
In the light of the above statements, choose the most appropriate answer from the options given below:
(a) Both Statement I and Statement II are true 
(b) Statement I is false but Statement II is true 
(c) Both Statement I and Statement II are false 
(d) Statement I is true but Statement II is false 

Ans. d
Given Statement I is true as in a number of processes, one element is used to reduce the oxide of another metal. Any element will reduce the oxide of other metal which lie above it in the Ellingham diagram because the free energy change will become more negative.
Given Statement II is false as the value of ΔS is decreases from left to right in Ellingham diagram.

Q.40. The addition of silica during the extraction of copper from its sulphide ore             (JEE Main 2021)
(a) Converts copper sulphide into copper silicate
(b) Converts iron oxide into iron silicate
(c) Reduces copper sulphide into metallic copper
(d) Reduces the melting point of the reaction mixture

Ans. b
Silica is used to remove FeO impurity from the ore of copper

Q.41. Which one of the following set of elements can be detected using sodium fusion extract?             (JEE Main 2021)
(a) Sulfur, Nitrogen, Phosphorous, Halogens
(b) Phosphorous, Oxygen, Nitrogen, Halogens
(c) Nitrogen, Phosphorous, Carbon, Sulfur
(d) Halogens, Nitrogen, Oxygen, Sulfur

Ans. a
By sodium fusion extract we can detect Sulphur, Nitrogen, Phosphorous and Halogens, because they are converted in to their ionic form with sodium metal.

Q.42. The statement is incorrect about Ellingham diagram is             (JEE Main 2021)
(a) Provides idea about the reaction rate.
(b) Provides idea about free energy change.
(c) Provides idea about changes in the phases during the reaction.
(d) Provides idea about reduction of metal oxide.

Ans. a
Ellingham diagram is a plot between ΔG^∘ and T and does not give any information regarding rate of reaction.

Q.43. Match List I with List II : (Both having metallurgical terms)             (JEE Main 2021)

Choose the correct answer from the options given below:
(a) (a)-(iii), (b)-(ii), (c)-(i), (d)-(iv) 
(b) (a)-(iii), (b)-(iv), (c)-(i), (d)-(ii) 
(c) (a)-(iv), (b)-(i), (c)-(iii), (d)-(ii) 
(d) (a)-(iv), (b)-(iii), (c)-(ii), (d)-(i) 

Ans. a
(a) Concentration of Ag is performed by leaching with dilute NaCN solution
(b) Pig iron is formed in blast furnace
(c) Blister Cu is produced in Bessemer converter
(d) Froth floatation method is used for sulphide ores.
Note: During extraction of Cu reverberatory furnace is involved.

Q.44. In the leaching of alumina from bauxite, the ore expected to leach out in the process by reacting with NaOH is:             (JEE Main 2021)
(a) TiO₂
(b) Fe₂O₃
(c) ZnO
(d) SiO₂

Ans. d
In bauxite impurities of Fe₂O₃, TiO₂ and SiO₂ are present, Fe₂O₃ and TiO₂ are basic oxides therefore does not reacts with or dissolve in NaOH whereas SiO₂ is acidic oxide it gets dissolve in NaOH, hence leach out 

Q.45. Sulphide ion is soft base and its ores are common for metals.             (JEE Main 2021)
(a) Pb
(b) Al
(c) Ag
(d) Mg

Ans. a, c
Pb and Ag commonly exist in the form of sulphide ore like Pbs (galena) and Ag₂S (Argentite) 'Al' is mainly found in the form of oxide ore whereas 'Mg' is found in the form of halide ore.

Q.46. Consider two chemical reactions (A) and (B) that take place during metallurgical process:             (JEE Main 2021)


The correct option of names given to them respectively is:
(a) (A) is calcination and (B) is roasting
(b) Both (A) and (B) are producing same product so both are roasting
(c) Both (A) and (B) are producing same product so both are calcination
(d) (A) is roasting and (B) is calcination

Ans. a

Heating in absence of oxygen in calcination. 

Heating in presence of oxygen in roasting. 
Hence, (A) is calcination while (B) in roasting. 

Q.47. The metal that can be purified economically by fractional distillation method is:             (JEE Main 2021)
(a) Fe
(b) Zn
(c) Cu
(d) Ni

Ans. b
Zinc can be purified economically by fractional distillation. Fractional distillation process utilises the boiling point difference between metal and that of impurity. Using this process, crude zinc containing Cd, Fe and Pb as impurities can be refined.

Q.48. An inorganic Compound 'X' on treatment with concentrated H₂SO₄ produces brown fumes and gives dark brown ring with FeSO₄ in presence of concentrated H₂SO₄. Also Compound 'X' gives precipitate 'Y', when its solution in dilute HCl is treated with H₂S gas. The precipitate 'Y' on treatment with concentrated HNO₃ followed by excess of NH₄OH further gives deep blue coloured solution, Compound 'X' is:              (JEE Main 2021)
(a) Co(NO₃)₂
(b) Pb(NO₂)₂
(c) Cu(NO₃)₂
(d) Pb(NO₃)₂

Ans. c
Compound ‘X’ is copper nitrate, i.e. Cu(NO₃)₂ is an inorganic compound. On treatment with concentrated H₂SO₄ produces brown fumes and gives dark brown ring with FeSO₄ in presence of concentrated H₂SO₄. Chemical reaction is as follows


Cu²⁺ is a group II cation with group II reagents (HCl/H₂S) , it gives black coloured precipitates. These precipitates gives blue colour solution on treatment with HNO₃ followed by excess of NH₄OH.

Q.49. Given below are two statements. One is labelled as Assertion A nd the other is labelled as Reason R.
Assertion A: Sharp glass edge becomes smooth on heating it upto its melting point.
Reason R: The viscosity of glass decreases on melting.
Choose the most appropriate answer from the options given below.              (JEE Main 2021)
(a) A is true but R is false
(b) Both A and R are true but R is NOT the correct explanation of A.
(c) A is false but R is true.
(d) Both A and R are true and R is the correct explanation of A.

Ans. b
On heating the glass, it melts and takes up rounded shape at the edges, which has minimum surface area. This is due to the property of surface tension of liquids and not due to decrease in viscosity.
Viscosity generally decreases as the temperature increases.
Hence, both A and R are true but R is not the correct explanation of A.

Q.50. Match List - I with List - II:              (JEE Main 2021)

Choose the most appropriate answer from the option given below:
(a) (a)-(ii), (b)-(iii), (c)-(iv), (d)-(i) 
(b) (a)-(ii), (b)-(iv), (c)-(iii), (d)-(i) 
(c) (a)-(ii), (b)-(iii), (c)-(i), (d)-(iv) 
(d) (a)-(i), (b)-(iv), (c)-(ii), (d)-(iii)

Ans. a
(a) Mercury → Distillation refining
(b) Copper → Electrolytic refining
(c) Silicon → Zone refining
(d) Nickel → Vapour phase refining

Q.51. The chemical that is added to reduce the melting point of the reaction mixture during the extraction of aluminium is:              (JEE Main 2021)
(a) Cryolite
(b) Bauxite
(c) Calamine
(d) Kaolite

Ans. a
Alumina is mixed with Na₃AlF₆ (Cryolite) and CaF₂ to lower the melting point of mixture.

Q.52. Match List - I with List - II:              (JEE Main 2021)

Choose the correct answer from the options given below:
(a) (a)-(i), (b)-(iii), (c)-(ii), (d)-(iv)
(b) (a)-(ii), (b)-(i), (c)-(iv), (d)-(iii)
(c) (a)-(ii), (b)-(iii), (c)-(i), (d)-(iv)
(d) (a)-(iv), (b)-(i), (c)-(ii), (d)-(iii)

Ans. b
(a) Haematite → (ii) Fe₂O₃
(b) Bauxite → (i) Al₂O₃.xH₂O
(c) Magnetite → (iv) Fe₃O₄
(d) Malachite → (iii) CuCO₃.Cu(OH)₂

Q.53. The point of intersection and sudden increase in the slope, in the diagram given below, respectively, indicates:              (JEE Main 2021)
(a) ΔG > 0 and decomposition of the metal oxide
(b) ΔG < 0 and decomposition of the metal oxide
(c) ΔG = 0 and reduction of the metal oxide
(d) ΔG = 0 and melting or boiling point of the metal oxide

Ans. d
From the Ellingham diagram given, the point of intersection represents ΔG = 0 and the temperature at which sudden increase in the slope occurs is indicated by melting or boiling.

Q.54. Which of the following reduction reaction CANNOT be carried out with coke?              (JEE Main 2021)
(a) ZnO → Zn
(b) Fe₂O₃ → Fe
(c) Cu₂O → Cu
(d) Al₂O₃ → Al

Ans. d
Al₂O₃ is reduced by the electrolytic reduction method.

Q.55. The process that involves the removal of sulphur from the ores is:              (JEE Main 2021)
(a) Roasting
(b) Smelting
(c) Leaching
(d) Refining

Ans. a
Removal of sulphur from the ore is done by Roasting.

Q.56. Calgon is used for water treatment. Which of the following statement is NOT true about Calgon?              (JEE Main 2021)
(a) It is also known as Graham's salt.
(b) It is polymeric compound and is water soluble.
(c) It does not remove Ca²⁺ ion by precipitation.
(d) Calgon contains the 2^nd most abundant element by weight in the Earth's crust.

Ans. d
Calgon is sodium hexametaphosphate, a polymeric compound also called as Graham’s salt.
Order of abundance of element in earth crust is
O > Si > Al > Fe > Ca > Na > Mg > K
So second most abundant element in earth crust is Si not Ca. 

Q.57. Match List - I with List - II.              (JEE Main 2021)

Choose the correct answer from the options given below:
(a) (a) → (i), (b) → (ii), (c) → (iii), (d) → (iv)
(b) (a) → (iii), (b) → (i), (c) → (v), (d) → (ii)
(c) (a) → (i), (b) → (ii), (c) → (v), (d) → (iii)
(d) (a) → (iii), (b) → (v), (c) → (i), (d) → (iv) 

Ans. d
Siderite → FeCO₃
Calamine → ZnCO₃
Malachite → CuCO₃.Cu(OH)₂
Cryolite → Na₃AlF₆
Note : ( Remember all those ores names. Any one of those can be asked in the exam.)
Oxides Ores :
(1) ZnO - Zincite
(2) Fe₂O₃ - Haematite
(3) Fe₃O₄ - Magnetite (FeO + Fe₂O₃ mixture)
(4) Fe₂O₃ . 3H₂O - Limonite
(5) MnO₂ - Pyrolusite
(6) Cu₂O - Cuprite or Ruby Copper
(7) TiO₂ - Rutile
(8) FeCr₂O₄ - Chromite (FeO + Cr₂O₃)
(9) FeTiO₃ - Illmenite (FeO + TiO₂)
(10) Na₂B₄O₇ . 10H₂O - Borax or Tincal
(11) U₃O₈ - Pitch Blende
(12) SnO₂ - Tin Stone or Cassiterite
(13) Ca₂B₆O₁₁ . 5H₂O - Colemanite (2 Cao + 3 B₂O₃)
(14) Al₂O₃ . 2H₂O - Bauxite
(15) Al₂O₃ . H₂O - Diaspore
(16) Al₂O₃ - Corundum
Sulphides Ores :
(1) ZnS - Zinc Blende or Sphalerite
(2) PbS - Galena
(3) Ag₂S - Argentite or Silver Glance
(4) HgS - Cinnabar
(5) Cu₂S - Chalcocite or Copper glance
(6) CuFeS₂ - Copper pyrites or Chalco pyrites (Cu₂S + Fe₂S₃ mixture)
(7) FeS₂ - Iron pyrites or Fool's Gold
(8) 3Ag₂S . Sb₂S₂ - Pyrargyrite or ruby silver
Halides Ores :
(1) NaCl - Rock Salt
(2) KCl - Sylvine
(3) Na₃AlF₆ - Cryolite [3NaF + AlF₆]
(4) CaF₂ - Fluorspar
(5) KCl . MgCl₂ . 6H₂O - Carnalite
(6) AgCl - Horn Silver
Carbonates Ores :
(1) CaCO₃ - Limestone
(2) MgCO₃ - Magnesite
(3) CaCO₃ . MgCO₃ - Dolomite
(4) ZnCO₃ - Calamine
(5) PbCO₃ - Cerrusite
(6) FeCO₃ - Siderite
(7) CuCO₃ . Cu(OH)₂ or Cu₂CO₃(OH)₂ - Malachite or Basic Copper Carbonates
(8) 2 CuCO₃ . Cu(OH)₂ - Azurite
Sulphates Ores :
(1) CuSO₄ . 2H₂O - Gypsum
(2) MgSO₄ . 7H₂O - Epson Salt
(3) Na₂SO₄ . 10 H₂O - Glauber's Salt
(4) PbSO₄ - Anglesite
(5) ZnSO₄ . 7H₂O - White Vitriol
(6) FeSO₄ . 7H₂O - Green Vitriol
(7) CuSO₄ . 5H₂O - Blue Vitriol or Chalcanthite
Nitrate Ores :
(1) KNO₃ - Indian Saltpetre
(2) NaNO₃ - Chile Saltpetre
Arsenides Ores :
(1) NiAs - Kupfernickel
(2) NiAsS - Nickel glance 

Q.58. Match List - I with List - II.              (JEE Main 2021)

Choose the correct answer from the options given below:
(a) (a) → (iv), (b) → (iii), (c) → (i), (d) → (ii) 
(b) (a) → (iv), (b) → (i), (c) → (ii), (d) → (iii) 
(c) (a) → (iii), (b) → (ii), (c) → (i), (d) → (iv) 
(d) (a) → (i), (b) → (iii), (c) → (iv), (d) → (ii)

Ans. a
(a) Sodium carbonate is prepared by Solvay process
(b) Titanium is refined by Van-Arkel process
(c) Chlorine is prepared by Deacon process
(d) Sodium hydroxide is prepared by Castner-Kellner process

Q.59. Match List - I with List - II.              (JEE Main 2021)

Choose the most appropriate answer from the options given below:
(a) (a) → (i), (b) → (iii), (c) → (iv), (d) → (ii) 
(b) (a) → (iii), (b) → (i), (c) → (ii), (d) → (iv) 
(c) (a) → (ii), (b) → (i), (c) → (iv), (d) → (iii) 
(d) (a) → (ii), (b) → (iv), (c) → (i), (d) → (iii)

Ans. c
Kernite : Na₂B₄O₇.4H₂O (Boron)
Cassiterite : SnO₂ (Tin)
Calamine : ZnCO₃ (Zinc)
Cryolite : Na₃AlF₆ (Fluorine)
Note : ( Remember all those ores names. Any one of those can be asked in the exam.)
Oxides Ores :
(1) ZnO - Zincite
(2) Fe₂O₃ - Haematite
(3) Fe₃O₄ - Magnetite (FeO + Fe₂O₃ mixture)
(4) Fe₂O₃ . 3H₂O - Limonite
(5) MnO₂ - Pyrolusite
(6) Cu₂O - Cuprite or Ruby Copper
(7) TiO₂ - Rutile
(8) FeCr₂O₄ - Chromite (FeO + Cr₂O₃)
(9) FeTiO₃ - Illmenite (FeO + TiO₂)
(10) Na₂B₄O₇ . 10H₂O - Borax or Tincal
(11) U₃O₈ - Pitch Blende
(12) SnO₂ - Tin Stone or Cassiterite
(13) Ca₂B₆O₁₁ . 5H₂O - Colemanite (2 Cao + 3 B₂O₃)
(14) Al₂O₃ . 2H₂O - Bauxite
(15) Al₂O₃ . H₂O - Diaspore
(16) Al₂O₃ - Corundum
Sulphides Ores :
(1) ZnS - Zinc Blende or Sphalerite
(2) PbS - Galena
(3) Ag₂S - Argentite or Silver Glance
(4) HgS - Cinnabar
(5) Cu₂S - Chalcocite or Copper glance
(6) CuFeS₂ - Copper pyrites or Chalco pyrites (Cu₂S + Fe₂S₃ mixture)
(7) FeS₂ - Iron pyrites or Fool's Gold
(8) 3Ag₂S . Sb₂S₂ - Pyrargyrite or ruby silver
Halides Ores :
(1) NaCl - Rock Salt
(2) KCl - Sylvine
(3) Na₃AlF₆ - Cryolite [3NaF + AlF₆]
(4) CaF₂ - Fluorspar
(5) KCl . MgCl₂ . 6H₂O - Carnalite
(6) AgCl - Horn Silver
Carbonates Ores :
(1) CaCO₃ - Limestone
(2) MgCO₃ - Magnesite
(3) CaCO₃ . MgCO₃ - Dolomite
(4) ZnCO₃ - Calamine
(5) PbCO₃ - Cerrusite
(6) FeCO₃ - Siderite
(7) CuCO₃ . Cu(OH)₂ or Cu₂CO₃(OH)₂ - Malachite or Basic Copper Carbonates
(8) 2 CuCO₃ . Cu(OH)₂ - Azurite
Sulphates Ores :
(1) CuSO₄ . 2H₂O - Gypsum
(2) MgSO₄ . 7H₂O - Epson Salt
(3) Na₂SO₄ . 10 H₂O - Glauber's Salt
(4) PbSO₄ - Anglesite
(5) ZnSO₄ . 7H₂O - White Vitriol
(6) FeSO₄ . 7H₂O - Green Vitriol
(7) CuSO₄ . 5H₂O - Blue Vitriol or Chalcanthite
Nitrate Ores :
(1) KNO₃ - Indian Saltpetre
(2) NaNO₃ - Chile Saltpetre
Arsenides Ores :
(1) NiAs - Kupfernickel
(2) NiAsS - Nickel glance 

Q.60. The method used for the purification of Indium is:              (JEE Main 2021)
(a) zone refining
(b) vapour phase refining
(c) liquation
(d) van Arkel method

Ans. a
Zone refining is used for the purification of indium. 

Q.61. The major components of German Silver are:              (JEE Main 2021)
(a) Zn, Ni and Ag
(b) Cu, Zn and Ni
(c) Cu, Zn and Ag
(d) Ge, Cu and Ag

Ans. b
Composition of German Silver → 56% Cu + 24% Zn + 20% Ni
Note:

Q.62. Ellingham diagram is a graphical representation of:              (JEE Main 2021)
(a) ΔG vs P
(b) ΔG vs T
(c) (ΔG − TΔS) vs T
(d) ΔH vs T

Ans. b
Ellingham diagram is a graphical representation of ΔG vs T when metal heated with oxygen to form metal oxide.

Q.63. Math List - I with List - II.              (JEE Main 2021)

Choose the correct answer from the options given below:
(a) (a)-(iv), (b)-(iii), (c)-(ii), (d)-(i)
(b) (a)-(i), (b)-(ii), (c)-(iii), (d)-(iv)
(c) (a)-(iii), (b)-(i), (c)-(iv), (d)-(ii)
(d) (a)-(ii), (b)-(iv), (c)-(i), (d)-(iii)

Ans. c
Siderite → FeCO₃
Calamine → ZnCO₃
Kaolinite → Si₂Al₂O₅(OH)₄ or Al₂O₃.2SiO₂.2H₂O
Malachite → CuCO₃.Cu(OH)₂
Note : ( Remember all those ores names. Any one of those can be asked in the exam.)
Oxides Ores :
(1) ZnO - Zincite
(2) Fe₂O₃ - Haematite
(3) Fe₃O₄ - Magnetite (FeO + Fe₂O₃ mixture)
(4) Fe₂O₃ . 3H₂O - Limonite
(5) MnO₂ - Pyrolusite
(6) Cu₂O - Cuprite or Ruby Copper
(7) TiO₂ - Rutile
(8) FeCr₂O₄ - Chromite (FeO + Cr₂O₃)
(9) FeTiO₃ - Illmenite (FeO + TiO₂)
(10) Na₂B₄O₇ . 10H₂O - Borax or Tincal
(11) U₃O₈ - Pitch Blende
(12) SnO₂ - Tin Stone or Cassiterite
(13) Ca₂B₆O₁₁ . 5H₂O - Colemanite (2 Cao + 3 B₂O₃)
(14) Al₂O₃ . 2H₂O - Bauxite
(15) Al₂O₃ . H₂O - Diaspore
(16) Al₂O₃ - Corundum
Sulphides Ores :
(1) ZnS - Zinc Blende or Sphalerite
(2) PbS - Galena
(3) Ag₂S - Argentite or Silver Glance
(4) HgS - Cinnabar
(5) Cu₂S - Chalcocite or Copper glance
(6) CuFeS₂ - Copper pyrites or Chalco pyrites (Cu₂S + Fe₂S₃ mixture)
(7) FeS₂ - Iron pyrites or Fool's Gold
(8) 3Ag₂S . Sb₂S₂ - Pyrargyrite or ruby silver
Halides Ores :
(1) NaCl - Rock Salt
(2) KCl - Sylvine
(3) Na₃AlF₆ - Cryolite [3NaF + AlF₆]
(4) CaF₂ - Fluorspar
(5) KCl . MgCl₂ . 6H₂O - Carnalite
(6) AgCl - Horn Silver
Carbonates Ores :
(1) CaCO₃ - Limestone
(2) MgCO₃ - Magnesite
(3) CaCO₃ . MgCO₃ - Dolomite
(4) ZnCO₃ - Calamine
(5) PbCO₃ - Cerrusite
(6) FeCO₃ - Siderite
(7) CuCO₃ . Cu(OH)₂ or Cu₂CO₃(OH)₂ - Malachite or Basic Copper Carbonates
(8) 2 CuCO₃ . Cu(OH)₂ - Azurite
Sulphates Ores :
(1) CuSO₄ . 2H₂O - Gypsum
(2) MgSO₄ . 7H₂O - Epson Salt
(3) Na₂SO₄ . 10 H₂O - Glauber's Salt
(4) PbSO₄ - Anglesite
(5) ZnSO₄ . 7H₂O - White Vitriol
(6) FeSO₄ . 7H₂O - Green Vitriol
(7) CuSO₄ . 5H₂O - Blue Vitriol or Chalcanthite
Nitrate Ores :
(1) KNO₃ - Indian Saltpetre
(2) NaNO₃ - Chile Saltpetre
Arsenides Ores :
(1) NiAs - Kupfernickel
(2) NiAsS - Nickel glance 

Q.64. Which of the following ore is concentrated using group 1 cyanide salt?              (JEE Main 2021)
(a) Sphalerite
(b) Malachite
(c) Siderite
(d) Calamine

Ans. a
The chemical formulas of given ore in options are as follows

Sphalerite ore : ZnS

Calamine ore : ZnCO₃

Siderite ore : FeCO₃

Malachite ore : Cu(OH)₂.CuCO₃

Sphalerite ore containing ZnS is concentrated using group is cyanide salt (NaCN) as a depressant by froth flotation method.
Note : ( Remember all those ores names. Any one of those can be asked in the exam.)

Oxides Ores :

(1) ZnO - Zincite

(2) Fe₂O₃ - Haematite

(3) Fe₃O₄ - Magnetite (FeO + Fe₂O₃ mixture)

(4) Fe₂O₃ . 3H₂O - Limonite

(5) MnO₂ - Pyrolusite

(6) Cu₂O - Cuprite or Ruby Copper

(7) TiO₂ - Rutile

(8) FeCr₂O₄ - Chromite (FeO + Cr₂O₃)

(9) FeTiO₃ - Illmenite (FeO + TiO₂)

(10) Na₂B₄O₇ . 10H₂O - Borax or Tincal

(11) U₃O₈ - Pitch Blende

(12) SnO₂ - Tin Stone or Cassiterite

(13) Ca₂B₆O₁₁ . 5H₂O - Colemanite (2 Cao + 3 B₂O₃)

(14) Al₂O₃ . 2H₂O - Bauxite

(15) Al₂O₃ . H₂O - Diaspore

(16) Al₂O₃ - Corundum

Sulphides Ores :

(1) ZnS - Zinc Blende or Sphalerite

(2) PbS - Galena

(3) Ag₂S - Argentite or Silver Glance

(4) HgS - Cinnabar

(5) Cu₂S - Chalcocite or Copper glance

(6) CuFeS₂ - Copper pyrites or Chalco pyrites (Cu₂S + Fe₂S₃ mixture)

(7) FeS₂ - Iron pyrites or Fool's Gold

(8) 3Ag₂S . Sb₂S₂ - Pyrargyrite or ruby silver

Halides Ores :

(1) NaCl - Rock Salt

(2) KCl - Sylvine

(3) Na₃AlF₆ - Cryolite [3NaF + AlF₆]

(4) CaF₂ - Fluorspar

(5) KCl . MgCl₂ . 6H₂O - Carnalite

(6) AgCl - Horn Silver

Carbonates Ores :

(1) CaCO₃ - Limestone

(2) MgCO₃ - Magnesite

(3) CaCO₃ . MgCO₃ - Dolomite

(4) ZnCO₃ - Calamine

(5) PbCO₃ - Cerrusite

(6) FeCO₃ - Siderite

(7) CuCO₃ . Cu(OH)₂ or Cu₂CO₃(OH)₂ - Malachite or Basic Copper Carbonates

(8) 2 CuCO₃ . Cu(OH)₂ - Azurite

Sulphates Ores :

(1) CuSO₄ . 2H₂O - Gypsum

(2) MgSO₄ . 7H₂O - Epson Salt

(3) Na₂SO₄ . 10 H₂O - Glauber's Salt

(4) PbSO₄ - Anglesite

(5) ZnSO₄ . 7H₂O - White Vitriol

(6) FeSO₄ . 7H₂O - Green Vitriol

(7) CuSO₄ . 5H₂O - Blue Vitriol or Chalcanthite

Nitrate Ores :

(1) KNO₃ - Indian Saltpetre

(2) NaNO₃ - Chile Saltpetre

Arsenides Ores :

(1) NiAs - Kupfernickel

(2) NiAsS - Nickel glance

Q.65. The major components in "Gun Metal” are:              (JEE Main 2021)
(a) Al, Cu, Mg and Mn
(b) Cu, Ni and Fe
(c) Cu, Sn and Zn
(d) Cu, Zn and Ni

Ans. c
Composition of Gun metal → 90% Cu + 8% Sn + 2% Zn
Note:
 

Q.66. In the electrolytic refining of blister copper, the total number of main impurities, from the following, removed as anode mud is ______________              (JEE Main 2021)
Pb, Sb, Se, Te, Ru, Ag, Au and Pt

Ans. 6
Anode mud contains Sb, Se, Te, Ag, Au and Pt