The variation of molar conductivity with the concentration of an electrolyte (X) in an aqueous solution is shown in the given figure.

The electrolyte X is:

1. CH3COOH 2. KNO3
3. HCl 4. NaCl
Subtopic:   Kohlrausch Law & Cell Constant |
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The standard Gibbs energy for the given cell reaction in kJ mol–1 at 298 K is :
Zn(s)+Cu2+(aq)Zn2+(aq)+Cu(s)
Eº(cell) = 2V at 298 K
(Faraday’s constant, F = 96000 C mol–1)

1. –192 kJ mol–1 2. 192 kJ mol–1
3. –384 kJ mol–1 4. 384 kJ mol–1
Subtopic:  Relation between Emf, G, Kc & pH |
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An oxidation-reduction reaction in which 3 electrons are transferred has a G° of 17.37 kJ mol–1 at 25°C. The value of Ecello(in V) is A× 10–2. The value of A is-
(1 F = 96,500 C mol–1)
1. -6
2. 4
3. -8
4. 2

Subtopic:  Relation between Emf, G, Kc & pH |
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The gibbs energy change (in J) for the given reaction at  [Cu2+] = [Sn2+] = 1 M and 298K is-

Cu(s)+Sn2+(aq.)Cu2+(aq.)+Sn(s)
Esn2+|Sn0=-0.16V,ECu2+|Cu0=0.34V,
TakeF=96500Cmol-1

1. 97850 J

2. 3500 J

3. 45660 J

4. 96500 J

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For a given cell, a 0.1 molar solution has a resistance of \(20 \ \Omega\) and molar conductivity of \(0.154 \times 10^{-3} S~cm^2~mol^{-1} \).
The value of the cell constant is:
1. \(3.08 \times 10^{-7} cm^{-1}\) 2. \(30.8 \times 10^{-7} cm^{-1}\)
3. \(0.308 \times 10^{-9} cm^{-1}\) 4. \(4.08 \times 10^{-6} cm^{-1}\)
Subtopic:  Conductance & Conductivity |
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Consider the values of reduction potential:
\(\mathrm{Co}^{3+}+e^{-} \rightarrow \mathrm{Co}^{2+} ; E^{\circ}=+1.81 \mathrm{~V}\)
\(\mathrm{~Pb}^{4+}+2 e^{-} \rightarrow \mathrm{Pb}^{2+} ; E^{\circ}=+1.67 \mathrm{~V}\)
\(\mathrm{Ce}^{4+}+e^{-} \rightarrow C e^{3+} ; E^{\circ}=+1.61 \mathrm{~V}\)
\( \mathrm{Bi}^{3+}+3 e^{-} \rightarrow \mathrm{Bi} ; E^{\circ}=+0.20 \mathrm{~V}\)

The oxidizing power of the species will increase in the order of:

1.  \(C o^{3+}<C e^{4+}<B i^{3+}<P b^{4+}\)
2. \(\mathrm{Co}^{3+}<P b^{4+}<C e^{4+}<B i^{3+}\)
3. \(C e^{4+}<P b^{4+}<B i^{3+}<C o^{3+}\)
4. \(B i^{3+}<C e^{4+}<P b^{4+}<C o^{3+}\)
Subtopic:  Electrochemical Series |
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A solution of Ni(NO3)2 is electrolysed between platinum electrodes using 0.1 Faraday electricity. The number of moles of Ni that will be deposited at the cathode are:

1. 0.10 2. 0.05
3. 0.20 4. 0.15
Subtopic:  Faraday’s Law of Electrolysis |
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Compound A used as a strong oxidizing agent is amphoteric in nature. It is part of lead storage batteries. Compound A is :

1. PbO2

2. PbO

3. PbSO4

4. Pb3O4

Subtopic:  Batteries & Salt Bridge |
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For the given cell :

CusCu2+C1MCu2+C2MCus change in Gibbs energy G is negative, if:

1. C1=2C2

2. C2=C12

3. C1=C2

4. C2=2C1

Subtopic:  Nernst Equation |
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Emf of the following cell at 298 K in V is x × 10–2 . The cell is Zn|Zn2+ (0.1 M) || Ag+ (0.01 M) | Ag. The value of x is-
(Rounded off to the nearest integer)
\(\begin{aligned} & \text { Given; } \mathrm{E}_{\mathrm{Zn}^{2+}}^{\mathrm{o}} / \mathrm{Zn}=-0.76 \mathrm{~V} \\ & \mathrm{E}_{\mathrm{Ag}^{+} / \mathrm{Ag}}^{\mathrm{o}}=+0.80 \mathrm{~V} ; \frac{2.303 \mathrm{RT}}{\mathrm{F}}=0.059 \end{aligned}\)

1. 157
2. 147
3. 144
4. 154

Subtopic:  Nernst Equation |
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