On account of the disruption in education due to the corona pandemic, we're opening up our platform for teachers, free of cost. Know More →

JEE Main

Explore popular questions from General Principles and Processes of Isolation of Elements for JEE Main. This collection covers General Principles and Processes of Isolation of Elements previous year JEE Main questions hand picked by experienced teachers.

Select Subject

Physics

Chemistry

Mathematics

General Principles and Processes of Isolation of Elements

Correct Marks 4

Incorrectly Marks -1

Q 1. The ores that are concentrated by froth floatation method are:-

A

Carbonates

Sulphides

C

Oxides

D

Phosphates

Explanation

Correct Marks 4

Incorrectly Marks -1

Q 2. The method of Zone refining of metals is based on the principle of:

Greater solubility of the impurities in the molten state than in the solid.

B

Greater solubility of pure metal than that of impurity.

C

Higher melting point of the impurity than that of pure metal.

D

Greater noble character of the solid metal than that of the impurity.

Explanation

Correct Marks 4

Incorrectly Marks -1

Q 3. In purification of bauxite ore, it is mixed with coke and heated at {tex} 1800 ^ { \circ } \mathrm { C } {/tex} in presence of nitrogen. This is:

A

Hall's process

Serpeck's process

C

Baeyer's process

D

Electrolytic reduction

Explanation

Correct Marks 4

Incorrectly Marks -1

Q 4. Select the reaction which does not occur in Bessemer's convertor:

A

{tex} \mathrm { FeS } + \mathrm { O } _ { 2 } \rightarrow \mathrm { FeO } + \mathrm { SO } _ { 2 } {/tex}

B

{tex} 2 \mathrm { Cu } _ { 2 } \mathrm { S } + 3 \mathrm { O } _ { 2 } \rightarrow 2 \mathrm { Cu } _ { 2 } \mathrm { O } + 2 \mathrm { SO } _ { 2 } {/tex}

C

{tex} \mathrm { FeO } + \mathrm { SiO } _ { 2 } \rightarrow \mathrm { FeSiO } _ { 3 } {/tex}

{tex} 2 \mathrm { CuFeS } _ { 2 } + \mathrm { O } _ { 2 } \rightarrow \mathrm { Cu } _ { 2 } \mathrm { S } + 2 \mathrm { FeS } + \mathrm { SO } _ { 2 } {/tex}

Explanation

Correct Marks 4

Incorrectly Marks -1

Q 5. Which of the following process is not involved in the extraction of Ag from argentite?

A

Hydrometallurgy

B

Formation of cyanide

Levigation

D

Reduction by Zn metal

Explanation

Correct Marks 4

Incorrectly Marks -1

Q 6. An example of an oxide ore is

Bauxite

B

Malachite

C

Zinc blende

D

Feldspar

Explanation

Correct Marks 4

Incorrectly Marks -1

Q 7. Which one of following beneficiation processes is used for the mineral {tex} \mathrm { Al } _ { 2 } \mathrm { O } _ { 3 } \cdot 2 \mathrm { H } _ { 2 } \mathrm { O } {/tex} ?

A

Froth floatation

Leaching

C

Liquation

D

Magnetic separation

Explanation

Correct Marks 4

Incorrectly Marks -1

Q 8. Cassiterite is concentrated by:

A

Levigation

Electromagnetic separation

C

Froth-floatation

D

Liquification

Explanation

Cassiterite or tin stone (SnO2​) is non-magnetic and found associated with magnetic impurities. Thus, it is concentrated by electromagnetic separation.

Correct Marks 4

Incorrectly Marks -1

Q 9. Gravity separation process may be used for the concentration of:

A

Chalcopyrite

B

Bauxite

Haematite

D

Calamine

Explanation

Correct Marks 4

Incorrectly Marks -1

Q 10. Bauxite is leached with:

A

{tex} \mathrm { KCN } {/tex}

B

{tex} \mathrm { NaCN } {/tex}

{tex} \mathrm { NaOH } {/tex}

D

{tex} \mathrm { Na } _ { 2 } \mathrm { CO } _ { 3 } {/tex}

Explanation

Correct Marks 4

Incorrectly Marks -1

Q 11. Which of the following factors is of no significance for roasting sulphide ores to the oxides and not subjecting the sulphide ores to carbon reduction directly?

A

Metal sulphides are thermodynamically more stable than {tex} \mathrm { CS } _ { 2 } {/tex}

B

{tex} \mathrm { CO } _ { 2 } {/tex} is thermodynamically more stable than {tex} \mathrm { CS } _ { 2 } {/tex}

Metal sulphides are less stable than the corresponding oxides

D

{tex} \mathrm { CO } _ { 2 } {/tex} is more volatile than {tex} \mathrm { CS } _ { 2 } {/tex}

Explanation




Correct Marks 4

Incorrectly Marks -1

Q 12. When the sample of copper wth zinc impurity is to be purified by electrolysis, the appropriate electrodes are in pair of cathode : anode

A

pure zinc {tex} : {/tex} pure copper

B

impure sample : pure copper

C

impure zinc {tex} : {/tex} impure sample

pure copper {tex} : {/tex} impure sample.

Explanation


Correct Marks 4

Incorrectly Marks -1

Q 13. The metal extracted by leaching with a cyanide is

A

{tex} \mathrm { Mg } {/tex}

{tex} \mathrm { Ag } {/tex}

C

{tex} \mathrm { Cu } {/tex}

D

{tex} \mathrm { Na } {/tex}

Explanation



Correct Marks 4

Incorrectly Marks -1

Q 14. In the cyanide extraction process of silver from argentite ore, the oxidizing and reducing agents used are

A

{tex} \mathrm { O } _ { 2 } {/tex} and {tex} \mathrm { CO } {/tex} respectively

{tex} \mathrm { O } _ { 2 } {/tex} and {tex} \mathrm { Zn } {/tex} dust respectively

C

{tex} \mathrm { HNO } _ { 3 } {/tex} and {tex} \mathrm { Zn } {/tex} dust respectively

D

{tex} \mathrm { HNO } _ { 3 } {/tex} and {tex} \mathrm { CO } {/tex} respectively

Explanation

Correct Marks 4

Incorrectly Marks -1

Q 15. The purpose of adding {tex} \mathrm { Na } _ { 3 } \mathrm { AlF } _ { 6 } {/tex} to {tex} \mathrm { Al } _ { 2 } \mathrm { O } _ { 3 } {/tex} during electrolysis is:-

A

To decrease melting point of {tex} \mathrm { Al } _ { 2 } \mathrm { O } _ { 3 } {/tex}

B

To increase conductivity of electrolyte

C

To provide reducing conditions in the bath

Both (a) and (b)

Explanation


Correct Marks 4

Incorrectly Marks -1

Q 16. Which of the following is not correctly matched?

A

{tex} \mathrm { ZnCO } _ { 3 } \rightarrow {/tex} Zn (Calcination followed by smelting)

{tex} \mathrm { Al } ( \mathrm { OH } ) _ { 3 } \rightarrow {/tex} Al (Calcination followed by smelting)

C

{tex} \mathrm { PbS } \rightarrow {/tex} Pb (Partial roasting followed by self reduction)

D

{tex} \mathrm { Cu } _ { 2 } \mathrm { S } \rightarrow {/tex} Cu (Complete roasting following by carbon reduction)

Explanation







Correct Marks 4

Incorrectly Marks -1

Q 17. When an impurity in metal has greater affinity for oxygen and is more easily oxidized than metal itself then the metal is refined by:

Cupellation

B

Zone refining

C

Poling

D

Electrolytic process

Explanation

Correct Marks 4

Incorrectly Marks -1

Q 18. What is the appropriate process for the extraction of lead from galena?
(A) Froth floatation (B) Calcination (C) Roasting (D) Self reduction (E) Electrolytic reduction (F) smelting (G) Leaching

A

{tex} \mathrm { G } \rightarrow \mathrm { B } \rightarrow \mathrm { D } \rightarrow \mathrm { E } {/tex}

{tex} A \rightarrow C \rightarrow D {/tex}

C

{tex} \mathrm { A } \rightarrow \mathrm { C } \rightarrow \mathrm { E } {/tex}

D

{tex} \mathrm { A } \rightarrow \mathrm { C } \rightarrow \mathrm { F } {/tex}

Explanation

Correct Marks 4

Incorrectly Marks -1

Q 19. Select the incorrect statement:

A

Based on reactivity series, occurrence of certain elements takes place in native state.

B

Due to the basic nature of oxides of alkaline earth metals, they combine with atmospheric acidic oxides giving salts.

C

Chalcopyrite ore contains both {tex} \mathrm {Cu} {/tex} and {tex} \mathrm {Fe} {/tex} .

Both anglesite and cassiterite contain {tex} \mathrm { Pb } {/tex} .

Explanation

Correct Marks 4

Incorrectly Marks -1

Q 20. Which of the following is not correctly matched?

A

Removal of oxide impurity from impure Cu {tex} \rightarrow {/tex} Poling process

B

Removal of Pb impurity from impure {tex} \mathrm { Ag } \rightarrow {/tex} Cupellation

Obtaining wrought iron from cast iron {tex} \rightarrow {/tex} Bessemerisation

D

Refining of Nickel {tex} \rightarrow {/tex} Mond's process

Explanation

Correct Marks 4

Incorrectly Marks -1

Q 21. Which of the following statement is not correct?

Tin stone is speratated from non-magnetic impurity of wolframite by electrolytic separation.

B

CO acts as reducing agent is most parts of blast furnace during extraction of iron.

C

A silicate slag is obtained during the extraction of Cu from CuFeS, and iron from haematite.

D

In Puddling process, impurities present in cast iron are oxidized by haematite.

Explanation

Correct Marks 4

Incorrectly Marks -1

Q 22. Three most occurring elements into the earth crust are:

{tex} \mathrm { O } , \mathrm { Si } , \mathrm { Al } {/tex}

B

{tex}\mathrm{Si}, \mathrm { O } , \mathrm { Fe } {/tex}

C

{tex} \mathrm { Fe } , \mathrm { Ca } , \mathrm { Al } {/tex}

D

{tex} \mathrm { Si } , \mathrm { O } , \mathrm { N } {/tex}

Explanation

Correct Marks 4

Incorrectly Marks -1

Q 23. Which of the following set of elements mostly occur as sulphide ores?

A

{tex} \mathrm { Zn } , \mathrm { Cu } , \mathrm { Na } {/tex}

{tex} \mathrm { Zn } , \mathrm { Cu } , \mathrm { Pb } {/tex}

C

{tex} \mathrm { Fe } , \mathrm { Al } , \mathrm { Ti } {/tex}

D

{tex} \mathrm { Cu } , \mathrm { Ag } , \mathrm { Au } {/tex}

Explanation

Correct Marks 4

Incorrectly Marks -1

Q 24. Slag is formed by reaction between:

A

Impurities and coke

B

Impurities and ore

Impurities and flux

D

Flux and coke

Explanation