Electrochemistry

Q1 FREE PREVIEW

PYQ

From the following select the one which is not an example of corrosion? [Re-NEET 2024]

aRusting of iron object

bProduction of hydrogen by electrolysis of water

cTarnishing of silver

dDevelopment of green coating on copper and bronze ornaments

✓ Correct answer: b) Production of hydrogen by electrolysis of water

ExplanationThe option that is not an example of corrosion is: B. Production of hydrogen by electrolysis of water Explanation: A. Rusting of iron object is a type of corrosion where iron reacts with oxygen and moisture to form iron oxides (rust).C. Tarnishing of silver involves the formation of silver sulfide on the surface of silver items due to a reaction with sulfur compounds in the air.D. Development of green coating on copper and bronze ornaments is caused by the formation of copper carbonate or copper chloride, known as patina, which is also a form of corrosion.Option B refers to a chemical reaction in which water is split into hydrogen and oxygen gases through electrolysis, and is not related to the process of corrosion.

Q2 FREE PREVIEW

PYQ

The role of fluorspar, which is added in small quantities in the electrolysis reduction of alumina dissolved in fused cryolite, is

aas a catalyst

bto make fused mixture conducting

cto lower the melting temperature of the mixture

dto decrease the rate of oxidation of carbon at anode

✓ Correct answer: b) to make fused mixture conducting

ExplanationThe electrolysis of is carried out in the steel tank linked inside with graphite.The graphite lining serves as cathode.The anode is also made of graphite rods hanging in the molten mass the electrolyte consist of alumina dissolved in fused cryolite and .Cryolite lower the melting point of alumina to and . increase the fluidity of the mass, so that the liberated aluminum metal may sink at the bottom & it is tapped off.

Q3

PYQ

From the following select the one which is not an example of corrosion?

[Re-NEET 2024]

a

Rusting of iron object

b

Production of hydrogen by electrolysis of water

c

Tarnishing of silver

d

Development of green coating on copper and bronze ornaments

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q4

PYQ

The standard cell potential of the following cell

\(Zn|Z{n}^{{2}^{+}}(aq)||F{e}^{2+}(aq)∣Fe\)
is \(0.32 V\). Calculate the standard Gibbs energy change for the reaction:
\(Zn(s)+F{e}^{2+}(aq)\to Z{n}^{2+}(aq)+Fe(s)\)
(Given : \(1 F =96487 C\) )

[Re-NEET 2024]

a

\(-61.75kJmo{l}^{-1}\)

b

\(+5.006kJmo{l}^{-1}\)

c

\(-5.006kJmo{l}^{-1}\)

d

\(+61.75kJmo{l}^{-1}\)

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q5

PYQ

Mass in grams of copper deposited by passing \(9.6487\mathrm{A}\) current through a voltmeter containing copper sulphate solution for \(100\) seconds is (Given : Molar mass of \(\mathrm{Cu}:63{\mathrm{gmol}}^{-1}\), \(1\mathrm{F}=96487\mathrm{C})\)

[NEET 2024]

a

0.0315 g

b

3.15 g

c

0.315 g

d

31.5 g

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q6

PYQ

The standard cell potential of the following cell

\(Zn|Z{n}^{{2}^{+}}(aq)||F{e}^{2+}(aq)∣Fe\)
is \(0.32 V\). Calculate the standard Gibbs energy change for the reaction:
\(Zn(s)+F{e}^{2+}(aq)\to Z{n}^{2+}(aq)+Fe(s)\)
(Given : \(1 F =96487 C\) )

[Re-NEET 2024]

a

\(-61.75kJmo{l}^{-1}\)

b

\(+5.006kJmo{l}^{-1}\)

c

\(-5.006kJmo{l}^{-1}\)

d

\(+61.75kJmo{l}^{-1}\)

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q7

PYQ

From the following select the one which is not an example of corrosion?

[Re-NEET 2024]

a

Rusting of iron object

b

Production of hydrogen by electrolysis of water

c

Tarnishing of silver

d

Development of green coating on copper and bronze ornaments

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q8

PYQ

Mass in grams of copper deposited by passing \(9.6487\mathrm{A}\) current through a voltmeter containing copper sulphate solution for \(100\) seconds is (Given : Molar mass of \(\mathrm{Cu}:63\mathrm{g}{\mathrm{mol}}^{-1}\), \(1\mathrm{F}=96487\mathrm{C})\)

[NEET 2024]

a

0.0315 g

b

3.15 g

c

0.315 g

d

31.5 g

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q9

PYQ

The reaction \(\frac{1}{2} \mathrm{H}_{2}(\mathrm{~g})+\mathrm{AgCl}(\mathrm{s}) \rightleftharpoons \mathrm{H}^{+}(\mathrm{aq})+\mathrm{Cl}^{-}(\mathrm{aq})+\mathrm{Ag}(\mathrm{s})\) occurs in which of the given galvanic cell.

[JEE Main 2023, 8 Apr (Shift 1)]

a

\(\mathrm{Pt}\left|\mathrm{H}_{2}(\mathrm{~g})\right| \mathrm{KCl}\left(\mathrm{sol}^{\mathrm{n}}\right)|\mathrm{AgCl}(\mathrm{s})| \mathrm{Ag}\)

b

\(\mathrm{Pt}\left|\mathrm{H}_{2}(\mathrm{~g})\right| \mathrm{HCl}\left(\mathrm{sol}^{\mathrm{n}}\right)|\mathrm{AgCl}(\mathrm{s})| \mathrm{Ag}\)

c

\(\mathrm{Ag}|\mathrm{AgCl}(\mathrm{s})| \mathrm{KCl}\left(\mathrm{sol}^{\mathrm{n}}\right)|\mathrm{AgCl}(\mathrm{s})| \mathrm{Ag}\)

d

\(\mathrm{Pt}\left|\mathrm{H}_{2}(\mathrm{~g})\right| \mathrm{HCl}\left(\mathrm{sol}^{\mathrm{n}}\right)\left|\mathrm{AgNO}_{3}\left(\mathrm{sol}^{\mathrm{n}}\right)\right| \mathrm{Ag}\)

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q10

PYQ

The product, which is not obtained during the electrolysis of brine solution is

[JEE Main 2023, 6 Apr (Shift 2)]

a

\(NaOH\)

b

\(Cl _2\)

c

\(H _2\)

d

\(HCl\)

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q11

PYQ

The number of Faradays (F) required to produce \(20\mathrm{g}\) of calcium from molten \({\mathrm{CaCl}}_{2}\) (Atomic mass of \(\left.\mathrm{Ca}=40\mathrm{g}{\mathrm{mol}}^{-1}\right)\) is:

a

1

b

2

c

3

d

4

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q12

PYQ

The conductivity of centimolar solution of \(\mathrm{KCl}\) at \(25^\circ \mathrm{C}\) is \(0.0210{\mathrm{ohm}}^{-1}{\mathrm{cm}}^{-1}\) and the resistance of the cell containing the solution at \(25^\circ \mathrm{C}\) is \(60\mathrm{ohm}\). The value of cell constant is -

[NEET 2023]

a

\(3.28{\mathrm{cm}}^{-1}\)

b

\(1.26{\mathrm{cm}}^{-1}\)

c

\(3.34{\mathrm{cm}}^{-1}\)

d

\(1.34{\mathrm{cm}}^{-1}\)

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q13

PYQ

The molar conductivity of 0.007 M acetic acid is \(20{\mathrm{Scm}}^{2}{\mathrm{mol}}^{-1}\). What is the dissociation constant of acetic acid? Choose the correct option

\(\left[\begin{matrix}{\Lambda }_{{H}^{+}}^{º}=350Sc{m}^{2}mo{l}^{-1} \\ {\Lambda }_{C{H}_{3}CO{O}^{-}}^{º}=50Sc{m}^{2}mo{l}^{-1}\end{matrix}\right]\\\)

[NEET 2021]

a

\(2.50\times {10}^{-4}\)

b

\(1.75\times {10}^{-5}\)

c

\(2.50\times {10}^{-5}\)

d

\(1.75\times {10}^{-4}\)

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q14

PYQ

Electrode potential data are given below:
\(F{e}^{+3}(aq)+{e}^{-}\to F{e}^{+2}(aq);E^\circ =+0.77V\) \(A{l}^{+3}(aq)+3{e}^{-}\to Al(s);E^\circ =-1,66V\) \(B{r}_{2}(aq)+2{e}^{-}\to 2B{r}^{-}(aq);E^\circ =+1.08V\)
Based on the data, the reducing power of \(F{e}^{+2}\), Al and \(B{r}^{-}\) will increase in the order

(PYQ-2023)

a

\(B{r}^{-}

b

\(F{e}^{+2}

c

\(Al

d

\(Al

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q15

PYQ

The number of Faradays \( (\mathrm{F}) \) required to produce \( 20 \mathrm{~g} \) of calcium from molten \( \mathrm{CaCl}_{2} \) (Atomic mass of \( \mathrm{Ca}=40 \mathrm{~g} \mathrm{~mol}^{-1} \) ) is

[NEET 2020]

a

2

b

3

c

4

d

1

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q16

PYQ

Amongst the following, the form of water with the lowest ionic conductance at \( 298 \mathrm{~K} \) is :

[JEE Main 2020, 9 Jan (Shift 2)]

a

distilled water

b

sea water

c

water from a well

d

saline water used for intravenous injection

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q17

PYQ

Given below are two statements : one is labelled as Assertion \(\mathbf{A}\) and the other is labelled as Reason \(\mathbf{R}\) :

Assertion A : In equation \(\Delta_r \mathrm{G}=-\mathrm{nFE}_{\mathrm{cell}}\), value of \(\Delta_r \mathrm{G}\) depends on n.

Reasons \(\mathbf{R}\) : \(\mathrm{E}_{\text {cell }}\) is an intensive property and \(\Delta_r \mathrm{G}\) is an extensive property.

In the light of the above statements, choose the correct answer from the options given below :

a

Both \(\mathbf{A}\) and \(\mathbf{R}\) are true and \(\mathbf{R}\) is NOT the correct explanation of \(\mathbf{A}\).

b

\(\mathbf{A}\) is true but \(\mathbf{R}\) is false

c

\(\mathbf{A}\) is false but \(\mathrm{R}\) is true

d

Both \(\mathbf{A}\) and \(\mathbf{R}\) are true and \(\mathbf{R}\) is the correct explanation of \(\mathbf{A}\).

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q18

PYQ

Match List-I with List-II:

List-I (Conversion)	List-II (Number of Faraday required)
(A)	1 mol of \({\mathrm{H}}_{2}\mathrm{O}\mathrm{to}{\mathrm{O}}_{2}\)	(I)	3F
(B)	1 mol of \({\mathrm{MnO}}_{4}^{-}\mathrm{to}{\mathrm{Mn}}^{2+}\)	(II)	2F
(C)	1.5 mol of Ca from molten CaCl₂	(III)	1F
(D)	1 mol of FeO to Fe₂O₃	(IV)	5F

Choose the correct answer from the options given below:

[NEET 2024]

a

A-III, B-IV, C-II, D-I

b

A-II, B-IV, C-I, D-III

c

A-III, B-IV, C-I, D-II

d

A-II, B-III, C-I, D-IV

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q19

PYQ

Given below are two statements : one is labelled as Assertion \(\mathbf{A}\) and the other is labelled as Reason \(\mathbf{R}\) :

Assertion A : In equation \(\Delta_r \mathrm{G}=-\mathrm{nFE}_{\mathrm{cell}}\), value of \(\Delta_r \mathrm{G}\) depends on \(\mathrm{n}\).

Reasons \(\mathbf{R}\) : \(\mathrm{E}_{\text {cell }}\) is an intensive property and \(\Delta_r \mathrm{G}\) is an extensive property.

In the light of the above statements, choose the correct answer from the options given below :

[NEET 2023]

a

Both \(\mathbf{A}\) and \(\mathbf{R}\) are true and \(\mathbf{R}\) is NOT the correct explanation of \(\mathbf{A}\).

b

\(\mathbf{A}\) is true but \(\mathbf{R}\) is false

c

\(\mathbf{A}\) is false but \(\mathrm{R}\) is true

d

Both \(\mathbf{A}\) and \(\mathbf{R}\) are true and \(\mathbf{R}\) is the correct explanation of \(\mathbf{A}\).

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q20

PYQ

Identify the reaction from following having top position in EMF series (Standard reduction potential) according to their electrode potential at \(298 \) K

[Re-NEET 2020]

a

\(Fe ^{2+}+2 e ^{-} \rightarrow Fe ( s )\)

b

\(Au ^{3+}+3 e ^{-} \rightarrow Au ( s )\)

c

\(K ^{+}+1 e ^{-} \rightarrow K ( s )\)

d

\(Mg ^{2+}+2 e ^{-} \rightarrow Mg ( s )\)

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q21

PYQ

In a typical fuel cell, the reactants \(( R )\) and product \(( P )\) are

[Re-NEET 2020]

a

\(R = H _{2( g )}, O _{2( g )} ; P = H _2 O _{(\ell)}\)

b

\(R = H _{2( g )}, O _{2( g )}, Cl _{2( g )} ; P = HClO _{4( aq )}\)

c

\(R = H _{2( g )}, N _{2( g )} ; P = NH _{3( aq )}\)

d

\(R = H _{2( g )}, O _{2( g )} ; P = H _2 O _{2(\ell)}\)

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Practice more NEET Chemistry PYQs