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
What happens to the voltage in a galvanic cell when the salt bridge is removed?
1. The voltage drops to zero.
2. The voltage remains the same.
3. The voltage gradually increases.
4. The voltage rapidly increases.
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) |
Which of the following combinations correctly represents the relation for the emf of the cell?
1. | (a) and (b) | 2. | (c) and (d) |
3. | (b) and (d) | 4. | (c) and (a) |