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 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 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 |
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 |
At 298 K the Emf
of the following cell is:
\(\small{Pt|H_{2}(1 \ atm)|H^{+}(0.02 \ M) \ || \ H^{+}(0.01 \ M)|H_{2}(1 \ atm)|Pt}\)
1. - 0.017 V
2. 0.0295 V
3. 0.1 V
4. 0.059 V
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 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 |
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.
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 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