The specific conductance of a 0.1 M KCl solution at 23°C is 0.012 Ω-1cm-1.
The resistance of the cell containing the solution at the same temperature was found to be 55 Ω. The cell constant will be:

1. 0.142 cm–1
2. 0.66 cm–1
3. 0.918 cm–1
4. 1.12 cm–1

Subtopic:  Conductance & Conductivity |
 90%
Level 1: 80%+
Hints
Links

For the cell, Ti/Ti+(0.001M)||Cu2+(0.1M)|Cu, Ecello at

25 °C is 0.83 V. Ecell can be increased :

1. By increasing [Cu2+]

2. By increasing [Ti+]

3. By decreasing [Cu2+]

4. None of the above.

Subtopic:  Nernst Equation | Faraday’s Law of Electrolysis |
 73%
Level 2: 60%+
Hints
Links

The unit of specific conductance is:

1. ohm-1 cm-1 2. ohm cm
3. ohm cm-1 4. ohm-1 cm
Subtopic:  Conductance & Conductivity |
 83%
Level 1: 80%+
Hints

advertisementadvertisement

The metal that cannot be produced upon reduction of its oxide by aluminium is :

1. K 2. Mn
3. Cr 4. Fe
Subtopic:  Electrode & Electrode Potential |
 72%
Level 2: 60%+
Hints
Links

Adiponitrile is manufactured electrolytically from acrylonitrile. The reaction is as follows:
CH2= CHCN → CN – (CH2 )4 – CN

How many kg of adiponitrile (molecular mass = 108) is produced in 9.65 hr using a current of 3750 A with 80 % efficiency?

1. 30 kg                                               

2. 58 kg

3. 60 kg                                               

4. 80 kg

Subtopic:  Faraday’s Law of Electrolysis |
 62%
Level 2: 60%+
Hints
Links

The useful work of the reaction \(\small{\mathrm{Ag}(\mathrm{s})+1 / 2 \mathrm{Cl}_2(\mathrm{~g}) \rightarrow \mathrm{AgCl}(\mathrm{s})}\) is: 

Given,
\(E_{Cl_{2}/Cl^{-}}^{o} \ = \ +1.36 \ V, \)
\(E_{AgCl/Ag, / Cl^{-}}^{o} \ = \ 0.22 \ V, \)
\( P_{Cl_{2}} \ = \ 1 \ atm\ and \)
\( T = 298 K\)

1. -110 kJ/mol 2. 220 kJ/mol
3. 55 kJ/mol 4. 1000 kJ/mol
Subtopic:  Relation between Emf, G, Kc & pH |
 71%
Level 2: 60%+
Hints
Links

advertisementadvertisement

Consider the given cell:

Pt(s) | H₂(g, 1 bar) | H⁺ (0.030 M) || Br⁻ (0.010 M) | Br₂(l) | Pt(s)

If the concentration of Br⁻ ions is doubled and the concentration of H⁺ ions is reduced to half of its initial value,
how will the emf of the cell change?

1. Two times
2. Four times
3. Eight times
4. Remains the same

Subtopic:  Nernst Equation |
 56%
Level 3: 35%-60%
Hints
Links

Aluminium metal can be produced by the electrolysis of molten aluminium oxide at about 1000 °C.
The cathode reaction is: \(Al^{3 +} + 3 e^{-} \rightarrow Al\)

Given that the atomic mass of aluminium is 27 amu and 1 Faraday = 96,500 C, calculate the quantity of electricity (in coulombs) required to produce 5.12 kg of aluminium by this method:

1. \(5 . 49 \times 10^{1 } C\) of electricity

2. \(5 . 49 \times 10^{4 } C\) of electricity

3. \(1 . 83 \times 10^{7 } C\) of electricity

4. \(5 . 49 \times 10^{7 } C\) of electricity

Subtopic:  Faraday’s Law of Electrolysis |
Level 4: Below 35%
Hints
Links

The specific conductance of 0.01 M solution of a weak monobasic acid is 0.20 x 10-3 S cm-1. The dissociation constant of the acid is:

[Given  ΛHA∞ = 400 S cm2 mol-1]

1. \(5 \times 10^{-2}\) 2. \(2.5 \times 10^{-5}\)
3. \(5 \times 10^{-4}\) 4. \(2.2 \times 10^{-11}\)
Subtopic:  Conductance & Conductivity |
 60%
Level 2: 60%+
Hints
Links

advertisementadvertisement

Calculate the standard cell potential, E°cell, in volts and the standard Gibbs free-energy change, ΔG°, in kJ mol⁻¹, respectively, for a two-electron redox reaction at 298 K having an equilibrium constant of 3.8 × 10⁻³.

1. -0.071, -13.8 2. -0.071, 13.8
3. 0.71, -13.8 4. 0.071, -13.8
Subtopic:  Relation between Emf, G, Kc & pH |
 65%
Level 2: 60%+
Hints