# JEE Main > General Principles and Processes of Isolation of Elements

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 popular teachers.

Physics
Chemistry
Maths

Q 1.

Correct4

Incorrect-1

Aluminium is extracted by the electrolysis of

A

bauxite

B

alumina

alumina mixed with molten cryolite

D

molten cryolite.

##### Explanation

Q 2.

Correct4

Incorrect-1

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

Q 3.

Correct4

Incorrect-1

Which one of the following ores is best concentrated by froth-flotation method?

A

Galena

B

Cassiterite

Magnetite

D

Malachite

##### Explanation

Q 4.

Correct4

Incorrect-1

During the process of electrolytic refining of copper, some metals present as impurity settle as 'anode mud'. These are

A

Fe and Ni

Ag and Au

C

Pb and Zn

D

Sn and Ag

##### Explanation

Q 5.

Correct4

Incorrect-1

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

Q 6.

Correct4

Incorrect-1

{tex}29.5 \mathrm { mg } {/tex} of an organic compound containing nitrogen was digested according to Kjeldahl's method and the evolved ammonia was absorbed in {tex}20 \mathrm { mL } {/tex} of {tex}0.1 \mathrm { M \ HCl } {/tex} solution. The
excess of the acid required {tex}15 \mathrm { mL } {/tex} of {tex}0.1 \mathrm { M \ } \mathrm { NaOH } {/tex} solution for complete neutralization. The percentage of nitrogen in the compound is

A

59

B

47.4

23.7

D

29.5

##### Explanation

Q 7.

Correct4

Incorrect-1

Which method of purification is represented by the following equation?
{tex} \mathrm { Ti } ( \mathrm { s } ) + 2 \mathrm { I } _ { 2 } ( \mathrm { g } ) \stackrel { 523 \mathrm { K } } { \longrightarrow } \mathrm { TiI } _ { 4 } ( \mathrm { g } ) \stackrel { 1700 \mathrm { K } } { \longrightarrow } \mathrm { Ti } ( \mathrm { s } ) + 2 \mathrm { I } _ { 2 } ( \mathrm { g } ) {/tex}

A

Zone refining

B

Cupellation

C

Polling

Van Arkel

##### Explanation

Q 8.

Correct4

Incorrect-1

The metal that cannot be obtained by electrolysis of an aqueous solution of its salts is:

A

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

{tex} \mathrm { Ca } {/tex}

C

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

D

{tex} \mathrm { Cr } {/tex}

##### Explanation

Q 9.

Correct4

Incorrect-1

In the context of the Hall-Heroult process for the extraction of Al, which of the following statements is false?

A

{tex} \mathrm { Al } ^ { 3 + } {/tex} is reduced at the cathode to form Al

{tex} \mathrm { Na } _ { 3 } \mathrm { AlF } _ { 6 } {/tex} serves as the electrolyte

C

{tex} \mathrm { CO } {/tex} and {tex} \mathrm { CO } _ { 2 } {/tex} are produced in this process

D

{tex} \mathrm { Al } _ { 2 } \mathrm { O } _ { 3 } {/tex} is mixed with CaF {tex} _ { 2 } {/tex} which lowers the melting point of the mixture and brings conductivit 112{tex} \mathrm { y } {/tex}

##### Explanation

Q 10.

Correct4

Incorrect-1

Which one of the following ores is best concentrated by froth floatation method?

Galena

B

Malachite

C

Magnetite

D

Siderite

##### Explanation

Q 11.

Correct4

Incorrect-1

Aluminium is extracted by the electrolysis of

A

bauxite

B

alumina

alumina mixed with molten cryolite

D

molten cryolite.

##### Explanation

Q 12.

Correct4

Incorrect-1

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

Q 13.

Correct4

Incorrect-1

Cyanide process is used for the extraction of

A

barium

B

aluminium

C

boron

silver

##### Explanation

Q 14.

Correct4

Incorrect-1

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

Q 15.

Correct4

Incorrect-1

Which one of the following ores is best concentrated by froth-flotation method?

A

Magnetite

B

Cassiterite

Galena

D

Malachite.

##### Explanation

Q 16.

Correct4

Incorrect-1

During the process of electrolytic refining of copper, some metals present as impurity settle as 'anode mud'. These are

A

Sn and Ag

B

Pb and Zn

Ag and Au

D

Fe and Ni

##### Explanation

Q 17.

Correct4

Incorrect-1

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?

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

B

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

C

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

D

Metal sulphides are less stable than the corresponding oxides

##### Explanation

Q 18.

Correct4

Incorrect-1

The chemical composition of slag formed during the extraction of copper is

A

{tex} \mathrm { Cu } _ { 2 } \mathrm { O } {/tex}

{tex} \mathrm { FeSiO } _ { 3 } {/tex}

C

{tex} \mathrm {CuFeS } _ { 2 } {/tex}

D

{tex} \mathrm { Cu } _ { 2 } \mathrm { S } + \mathrm { FeO } {/tex}

##### Explanation

Q 19.

Correct4

Incorrect-1

Zinc blende is concentrated by

A

Electromagnetic process

B

Calcination process

C

Distillation

Froth floatation process

##### Explanation

Q 20.

Correct4

Incorrect-1

Which of the following metal cannot be obtained by electrolysis of the aqueous solution of its salt?

A

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

B

{tex} \mathrm { Au } {/tex}

C

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

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

##### Explanation

Q 21.

Correct4

Incorrect-1

Purest form of iron is

A

Cast iron

B

Hard iron

C

Stainless steel

Wrought iron

##### Explanation

Q 22.

Correct4

Incorrect-1

The metal oxide which cannot be reduced to metal by carbon is

A

{tex} \mathrm { ZnO } {/tex}

B

{tex} \mathrm { Fe } _ { 2 } \mathrm { O } _ { 3 } {/tex}

C

{tex} \mathrm { PbO } {/tex}

{tex} \mathrm { Al } _ { 2 } \mathrm { O } _ { 3 } {/tex}

##### Explanation

Q 23.

Correct4

Incorrect-1

On heating a mixture of {tex} \mathrm { Cu } _ { 2 } \mathrm { O } {/tex} and {tex} \mathrm { Cu } _ { 2 } \mathrm { S } {/tex}, we get

{tex} \mathrm { Cu } + \mathrm { SO } _ { 2 } {/tex}

B

{tex} \mathrm { Cu } + \mathrm { SO } _ { 3 } {/tex}

C

{tex} \mathrm { CuO } + \mathrm { CuS } {/tex}

D

{tex} \mathrm { Cu } _ { 2 } \mathrm { SO } _ { 3 } {/tex}

##### Explanation

Q 24.

Correct4

Incorrect-1

Out of following which metal can be purified by Van Arkel method?

A

{tex}\mathrm {Ti} {/tex}

B

{tex}\mathrm{Z r} {/tex}

C

{tex} \mathrm { Hf } {/tex}

All of these

##### Explanation

Q 25.

Correct4

Incorrect-1

Froth floatation process is based on

A

Specific gravity of the ore particles

B

Magnetic properties of the ore particles

Wetting properties of the ore particles

D

Electrical properties of the ore particles