The pressure of H2 required to make the potential of H2 - electrode zero in pure water at 298 K is:
1. | 10–12 atm | 2. | 10–10 atm |
3. | 10–4 atm | 4. | 10–14 atm |
In the electrochemical cell:
Zn|ZnSO4(0.01 M) || CuSO4(1.0M),Cu, the emf of this Daniel cell is E1. When the concentration of ZnSO4 is changed to 1.0 M and that of CuSO4 is changed to 0.01 M, the emf changes to E2. The relationship between E1 and E2 is :
( Given, = 0.059)
1. E1 = E2
2. E1 < E2
3. E1 > E2
4. E2 = 0 E1
The electrode potential of Cu electrode dipped in 0.025 M CuSO4 solution at 298 K is:
(standard reduction potential of Cu = 0.34 V)
1. 0.047 V
2. 0.293 V
3. 0.35 V
4. 0.387 V
Consider the following cell reaction
2Fe(s) + (g) + 4(aq) 2(aq) + 2(l)
E° = 1.67 V, At [] = 10 M, = 0.1 atm and pH = 3, the cell potential at 25 °C is :
1. 1.27 V
2. 1.77 V
3. 1.87 V
4. 1.57 V
The voltage of the cell given below increases with:
Cell: Sn(s) + 2Ag+(aq) → Sn2+(aq) + 2Ag(s)
1. Increase in size of the silver rod.
2. Increase in the concentration of Sn2+ ions.
3. Increase in the concentration of Ag+ ions.
4. None of the above.
The electrode potential for Mg electrode varies according to the equation
\(E_{Mg^{2+}/Mg}\ = \ E_{Mg^{2+}/Mg}^{o} \ - \ \frac{0.059}{2}log\frac{1}{[Mg^{2+}]}\)
The graph of EMg2+ / Mg vs log [Mg2+] among the following is:
1. | 2. | ||
3. | 4. |
By how much will the potential of half cell Cu2+| Cu change if the solution is diluted to 100 times at 298 K. It will -
1. | Increase by 59 mV | 2. | Decrease by 59 mV |
3. | Increase by 29.5 mV | 4. | Decrease by 29.5 mV |
The change in reduction potential of a hydrogen electrode when its solution initialy at pH = 0 is neutralised to pH = 7, is a/an-
1. | Increase by 0.059 V | 2. | Decrease by 0.059 V |
3. | Increase by 0.41 V | 4. | Decrease by 0.41 V |
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.
If hydrogen electrodes dipped in two solutions of pH = 4 and pH = 6 are connected by a salt bridge, the emf of the resulting cell is -
1. 0.177 V
2. 0.3 V
3. 0.118 V
4. 0.104 V