Metallurgy · JEE Main previous year questions

2021 7 questions

1. Q772021 · 26 Aug 2021 · Shift 2

   Given below are two statements : Statement I : Sphalerite is a sulphide ore 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 froth flotation method. Choose the most appropriate answer from the options given below :

   1. A.Statement I is true but Statement II is false.
   2. B.Both Statement I and Statement II are true.
   3. C.Statement I is false but Statement II is true.
   4. D.Both Statement I and Statement II are false.
   Show answer

   Answer: B

2. Q802021 · 27 Jul 2021 · Shift 2

   The addition of silica during the extraction of copper from its sulphide ore :-

   1. A.converts copper sulphide into copper silicate
   2. B.converts iron oxide into iron silicate
   3. C.reduces copper sulphide into metallic copper
   4. D.reduces the melting point of the reaction mixture
   Show answer

   Answer: B

3. Q802021 · 25 Jul 2021 · Shift 1

   In the leaching of alumina from bauxite, the ore expected to leach out in the process by reacting with NaOH is :

   1. A.$\mathrm{Ti}{\mathrm{O}}_2$
   2. B.$\mathrm{F}{\mathrm{e}}_2{\mathrm{O}}_3$
   3. C.ZnO
   4. D.$\mathrm{Si}{\mathrm{O}}_2$
   Show answer

   Answer: D

4. Q782021 · 25 Jul 2021 · Shift 2

   Match List I with List II : (Both having metallurgical terms) $$\begin{array}{llll}& \text{List - I}& & \text{List - II}\\ \text{(a)}& \text{Concentration of Ag ore}& \text{(i)}& \text{Reverberatory furnace}\\ \text{(b)}& \text{Blast furnace}& \text{(ii)}& \text{Pig iron}\\ \text{(c)}& \text{Blister copper}& \text{(iii)}& \text{Leaching with dilute NaCN solution}\\ \text{(d)}& \text{Froth floatation method}& \text{(iv)}& \text{Sulfide ores}\end{array}$$ Choose the correct answer from the options given below :

   1. A.(a)-(iii), (b)-(ii), (c)-(i), (d)-(iv)
   2. B.(a)-(iii), (b)-(iv), (c)-(i), (d)-(ii)
   3. C.(a)-(iv), (b)-(i), (c)-(iii), (d)-(ii)
   4. D.(a)-(iv), (b)-(iii), (c)-(ii), (d)-(i)
   Show answer

   Answer: A

5. Q742021 · 22 Jul 2021 · Shift 2

   The water having more dissolved ${\mathrm{O}}_2$ is :

   1. A.boiling water
   2. B.water at $80^{\circ }\mathrm{C}$
   3. C.polluted water
   4. D.water at $4^{\circ }\mathrm{C}$
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   Answer: D

6. Q802021 · 22 Jul 2021 · Shift 2

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

   1. A.(a) and (c) only
   2. B.(a) and (d) only
   3. C.(a) and (b) only
   4. D.(c) and (d) only
   Show answer

   Answer: A

7. Q782021 · 26 Feb 2021 · Shift 1

   Match List - I with List - II. | List - I (Ore) | List - II (Element Present) | | :--- | :--- | | (a) Kernite | (i) Tin | | (b) Cassiterite | (ii) Boron | | (c) Calamine | (iii) Fluorine | | (d) Cryolite | (iv) Zinc | Choose the most appropriate answer from the options given below :

   1. A.(a) $\to$ (i), (b) $\to$ (iii), (c) $\to$ (iv), (d) $\to$ (ii)
   2. B.(a) $\to$ (iii), (b) $\to$ (i), (c) $\to$ (ii), (d) $\to$ (iv)
   3. C.(a) $\to$ (ii), (b) $\to$ (i), (c) $\to$ (iv), (d) $\to$ (iii)
   4. D.(a) $\to$ (ii), (b) $\to$ (iv), (c) $\to$ (i), (d) $\to$ (iii)
   Show answer

   Answer: C