Consider the following relations for emf of an electrochemical cell:
(a) | emf of cell = (Oxidation potential of anode) – (Reduction potential of cathode) |
(b) | emf of cell = (Oxidation potential of anode) + (Reduction potential of cathode) |
(c) | emf of cell = (Reduction potential of anode) + (Reduction potential of cathode) |
(d) | emf of cell = (Oxidation potential of anode) – (Oxidation potential of cathode) |
The correct relation among the given options is:
1. | (a) and (b) | 2. | (c) and (d) |
3. | (b) and (d) | 4. | (c) and (a) |
The correct expression that represents the equivalent conductance at infinite dilution of is:
(Given that are the equivalent conductances at infinite dilution of the respective ions)
1.
2.
3.
4.
Molar conductivities at infinite dilution of
NaCl, HCl, and are 126.4, 425.9, and 91.0 S cm2 mol–1 respectively.
for will be:
1. | \(180.5~S~cm^2~mol^{-1}\) | 2. | \(290.8~S~cm^2~mol^{-1}\) |
3. | \(390.5~S~cm^2~mol^{-1}\) | 4. | \(425.5~S~cm^2~mol^{-1}\) |
The Gibb's energy for the decomposition of \(\mathrm{A l_{2} O_{3}}\) at \(\mathrm{500~ ^\circ C}\) is as follows:
2/3Al2O3 → 4/3Al + O2 ; ∆rG = + 960 k J mol–1
The potential difference needed for the electrolytic reduction of aluminium oxide (Al2O3) at \(\mathrm{500~ ^\circ C}\) is at least,
1. 3.0 V
2. 2.5 V
3. 5.0 V
4. 4.5 V
coloumb charge liberated 1 gm silver (Ag). If the charge is doubled
then the amount of liberated Ag will be:
1. | 1 gm | 2. | 2 gm |
3. | 3 gm | 4. | 4 gm |
The concentration of solution will change when it is placed in a container which is made of:
1. | Al | 2. | Cu |
3. | Ag | 4. | None |
The cell reaction of an electrochemical cell is \(Cu^{2+}(C_{1}) + Zn \to Cu + Zn^{2+}(C_{2})\).
The change in free energy will be the function of:
\(1. \ ln (C_{1}+C_{2})\)
2. \(ln (\frac{C_{2}}{C_{1}})\)
\(3. \ ln C_{2}\)
\(4. \ lnC_{1}\)
4.5 g of aluminium (at. mass = 27 amu) is deposited at cathode from Al3+ solution by a certain quantity of electric charge. The volume of hydrogen produced at STP from H+ ions in solution by the same quantity of electric charge will be:
1. | 44.8 L | 2. | 11.2 L |
3. | 22.4 L | 4. | 5.6 L |
For the disproportionation of copper:
2Cu+ → C u2+ + C u is:
(Given for Cu+2/Cu is 0.34 V & Eº for Cu+2/Cu+ is 0.15 V )
1. 0.49 V
2. – 0.19 V
3. 0.38 V
4. – 0.38 V
A cell reaction become spontaneous when:
1. ∆Gº is negative
2. ∆Gº is positive
3. is positive
4. is negative