Metallurgy · JEE Main previous year questions

2023 17 questions

1. Q792023 · 13 Apr 2023 · Shift 2

   Given below are two statements related to Ellingham diagram: Statement I : Ellingham diagrams can be constructed for formation of oxides, sulfides and halides of metals. Statement II : It consists of plots of ${\Delta }_{\mathrm{f}}{\mathrm{H}}^0$ vs $\mathrm{T}$ for formation of oxides of elements. In the light of the above statements, choose the most appropriate answer from the options given below:

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

   Answer: C

2. Q762023 · 12 Apr 2023 · Shift 1

   Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R Assertion A : In the Ellingham diagram, a sharp change in slope of the line is observed for $\mathrm{Mg}\to \mathrm{MgO}$ at $\sim 1120^{\circ }\mathrm{C}$ Reason R: There is a large change of entropy associated with the change of state In the light of the above statements, choose the correct answer from the options given below

   1. A.Both A and R are true and R is the correct explanation of A
   2. B.A is false but R is true
   3. C.Both A and R are true but R is NOT the correct explanation of A
   4. D.A is true but R is false
   Show answer

   Answer: A

3. Q752023 · 11 Apr 2023 · Shift 2

   Given below are two statements : Statement I : In the metallurgy process, sulphide ore is converted to oxide before reduction. Statement II : Oxide ores in general are easier to reduce. In the light of the above statements, choose the most appropriate answer from the options given below:

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

   Answer: A

4. Q772023 · 10 Apr 2023 · Shift 1

   Which of the following is used as a stabilizer during the concentration of sulphide ores?

   1. A.Cresols
   2. B.Xanthates
   3. C.Fatty acids
   4. D.Pine oils
   Show answer

   Answer: A

5. Q642023 · 10 Apr 2023 · Shift 2

   Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R Assertion A : The energy required to form ${\text{Mg}}^{2+}$ from $\text{Mg}$ is much higher than that required to produce ${\text{Mg}}^{+}$ Reason R : ${\text{Mg}}^{2+}$ is a small ion and carries more charge than ${\text{Mg}}^{+}$ In the light of the above statements, choose the correct answer from the options given below.

   1. A.A is false but R is true
   2. B.Both A and R are correct but R is NOT the correct explanation of A
   3. C.Both A and R are correct and R is the correct explanation of A
   4. D.A is true but R is false
   Show answer

   Answer: C

6. Q802023 · 8 Apr 2023 · Shift 1

   Which of the following metals can be extracted through alkali leaching technique?

   1. A.$\mathrm{Sn}$
   2. B.$\mathrm{Cu}$
   3. C.$\mathrm{Au}$
   4. D.$\mathrm{Pb}$
   Show answer

   Answer: C

7. Q722023 · 8 Apr 2023 · Shift 2

   Given below are two statements: Statement I : Methyl orange is a weak acid. Statement II : The benzenoid form of methyl orange is more intense/deeply coloured than the quinonoid form. In the light of the above statement, choose the most appropriate answer from the options given below:

   1. A.Both Statement I and Statement II are incorrect
   2. B.Statement I is incorrect but Statement II is correct
   3. C.Both statement I and Statement II are correct
   4. D.Statement I is correct but Statement II is incorrect
   Show answer

   Answer: A

8. Q802023 · 6 Apr 2023 · Shift 1

   The possibility of photochemical smog formation is more at :

   1. A.Industrial areas
   2. B.Himalayan villages in winter
   3. C.The places with healthy vegetation
   4. D.Marshy lands
   Show answer

   Answer: A

9. Q742023 · 6 Apr 2023 · Shift 2
   
   1. A.B and D only
   2. B.B, C and D only
   3. C.A, B and D only
   4. D.A, B and C only
   Show answer

   Answer: D

10. Q892023 · 6 Apr 2023 · Shift 2· Numerical answer

    The number of colloidal systems from the following, which will have 'liquid' as the dispersion medium, is ___________. Gem stones, paints, smoke, cheese, milk, hair cream, insecticide sprays, froth, soap lather

    Show answer

    Answer: 5

11. Q752023 · 1 Feb 2023 · Shift 1

    Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R Assertion A: In an Ellingham diagram, the oxidation of carbon to carbon monoxide shows a negative slope with respect to temperature. Reason R: CO tends to get decomposed at higher temperature. In the light of the above statements, choose the correct answer from the options given below

    1. A.A is correct but R is not correct
    2. B.Both A and R are correct but R is NOT the correct explanation of A
    3. C.A is not correct but R is correct
    4. D.Both A and R are correct and R is the correct explanation of A
    Show answer

    Answer: A

12. Q762023 · 31 Jan 2023 · Shift 1

    The methods NOT involved in concentration of ore are A. Liquation B. Leaching C. Electrolysis D. Hydraulic washing E. Froth floatation Choose the correct answer from the options given below :

    1. A.A and C only
    2. B.C, D and E only
    3. C.B, D and C only
    4. D.B, D and E only
    Show answer

    Answer: A

13. Q762023 · 30 Jan 2023 · Shift 1

    In the extraction of copper, its sulphide ore is heated in a reverberatory furnace after mixing with silica to:

    1. A.remove $\mathrm{FeO}$ as ${\mathrm{FeSiO}}_3$
    2. B.remove calcium as ${\mathrm{CaSiO}}_3$
    3. C.decrease the temperature needed for roasting of ${\mathrm{Cu}}_2\mathrm{S}$
    4. D.separate $\mathrm{CuO}$ as ${\mathrm{CuSiO}}_3$
    Show answer

    Answer: A

14. Q802023 · 29 Jan 2023 · Shift 1

    The reaction representing the Mond process for metal refining is ____.

    1. A.$\mathrm{ZnO}+\mathrm{C}\stackrel{\mathrm{\Delta }}{\to }\mathrm{Zn}+\mathrm{CO}$
    2. B.$2K[\mathrm{Au}(\mathrm{CN}{)}_2]+\mathrm{Zn}\stackrel{\mathrm{\Delta }}{\to }{\mathrm{K}}_2[\mathrm{Zn}(\mathrm{CN}{)}_4]+2Au$
    3. C.$\mathrm{Zr}+2{\mathrm{I}}_2\stackrel{\mathrm{\Delta }}{\to }\mathrm{Zr}{\mathrm{I}}_4$
    4. D.$\mathrm{Ni}+4CO\stackrel{\mathrm{\Delta }}{\to }\mathrm{Ni}(\mathrm{CO}{)}_4$
    Show answer

    Answer: D

15. Q782023 · 29 Jan 2023 · Shift 2

    The major component of which of the following ore is sulphide based mineral?

    1. A.Sphalerite
    2. B.Siderite
    3. C.Malachite
    4. D.Calamine
    Show answer

    Answer: A

16. Q752023 · 25 Jan 2023 · Shift 2

    Given below are two statements : Statement I : In froth floatation method a rotating paddle agitates the mixture to drive air out of it. Statement II : Iron pyrites are generally avoided for extraction of iron due to environmental reasons. In the light of the above statements, choose the correct answer from the options given below :

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

    Answer: B

17. Q762023 · 24 Jan 2023 · Shift 2

    The metal which is extracted by oxidation and subsequent reduction from its ore is :

    1. A.Al
    2. B.Cu
    3. C.Ag
    4. D.Fe
    Show answer

    Answer: C