Given the following cell:
\(\small{Pt(s)|Br_{2}(l)|Br^{-}(0.010 \ M)\ || H_{2}(g)(1\ bar)|H^{+}(0.030 \ M)|Pt(s)}\)
If the concentration of \(Br^-\) becomes 2 times and the concentration of \(H^+\) becomes half of the initial value, then emf of the cell will become:
1. Two times.
2. Four times.
3. Eight times.
4. Remains the same.
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 |
Adiponitrile is manufactured electrolytically from acrylonitrile. The reaction is as follows:
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
The metal that cannot be produced upon reduction of its oxide by aluminium is :
1. | K | 2. | Mn |
3. | Cr | 4. | Fe |
The unit of specific conductance is:
1. | ohm-1 cm-1 | 2. | ohm cm |
3. | ohm cm-1 | 4. | ohm-1 cm |
For the cell, Ti/Ti+(0.001M)||Cu2+(0.1M)|Cu, 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.
The specific conductance of a 0.1 M KCl solution at 23 is 0.012 .
The resistance of the cell containing the solution at the same temperature
was found to be 55 . 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
Aluminium oxide may be electrolysed at 1000 C to furnish aluminium metal (Atomic mass = 27 amu; 1 Faraday = 96,500 Coulombs). The cathode reaction is:
To prepare 5.12 kg of aluminium metal by this method, would require :
1. of electricity
2. of electricity
3. of electricity
4. of electricity
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 = 400 S ]
1. | \(5 \times 10^{-2}\) | 2. | \(2.5 \times 10^{-5}\) |
3. | \(5 \times 10^{-4}\) | 4. | \(2.2 \times 10^{-11}\) |
The equilibrium constant of a 2 electron redox reaction at 298 K is 3.8 x . The cell potential Eo (in V) and the free energy change ∆Go (in kJ mol-1 ) for this equilibrium respectively, are -
1. | -0.071, -13.8 | 2. | -0.071, 13.8 |
3. | 0.71, -13.8 | 4. | 0.071, -13.8 |