If = -0.441 V and = 0.771 V, the standard emf of the reaction:
Fe + 2Fe3+→ 3Fe2+ will be:
1. | 0.330 V | 2. | 1.653 V |
3. | 1.212 V | 4. | 0.111 V |
Electrode potential is the potential difference between the -
1. Electrode and the electrolyte.
2. Anode and Cathode.
3. Anode and Atmosphere.
4. Cathode and Atmosphere.
The cell that will measure the standard electrode potential of a copper electrode is:
1. | \(1 \over 10\) bar) | H+(aq, 1M) || Cu2+(aq, 1M) | Cu Pt(s) | H2(g, |
2. | Pt(s) | H2(g, 1 bar) | H+(aq, 1M) || Cu2+ (aq, 2M) | Cu |
3. | Pt(s) | H2(g, 1 bar) | H+(aq, 1M)|| Cu2+ (aq, 1M) | Cu |
4. | \(1 \over 10\) bar) | H+(aq, \(1 \over 10\)M) || Cu2+(aq, 1M) | Cu Pt(s) | H2(g, |
The standard electrode potential for Sn4+/Sn2+ couple is +0.15 V and that for the Cr3+/Cr couple is -0.74 V. These two couples in their standard state are connected to make a cell. The cell potential will be:
1. | +0.89 V | 2. | +0.18 V |
3. | +1.83 V | 4. | +1.199 V |
The standard reduction potential for Fe2+|Fe and Sn2+|Sn electrodes are -0.44 V and -0.14 V respectively. For the cell reaction,
Fe2+ + Sn → Fe + Sn2+, the standard Emf is -
1. +0.30 V
2. 0.58 V
3. +0.58 V
4. -0.30 V
If a salt bridge is removed from the two half cells, the voltage:
1. Drops to zero.
2. Does not change.
3. Increases gradually.
4. Increases rapidly.
Zn2+(aq) + 2e–→ Zn(s) | Eo = – 0.76 V |
Ag2O(s) + H2O(l) + 2e– → 2Ag(s) + 2OH–(aq) | Eo = 0.34 V |
The cell potential will be:
1. | 0.42 V | 2. | 0.84 V |
3. | 1.34 V | 4. | 1.10 V |
A hypothetical electrochemical cell is shown below.
A|A+(x M) || B+(y M)|B
The Emf measured is +0.20 V. The cell reaction is:
1. A+ + B → A + B+
2. A+ + e- → A ; B+ + e- → B
3. The cell reaction cannot be predicted.
4. A + B+ → A+ + B
The difference between the electrode potentials of two electrodes when no current is drawn through the cell is called:
1. Cell potential.
2. Cell emf.
3. Potential difference.
4. Cell voltage.
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) |