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, \(\frac{R T}{F}\)= 0.059)
1. E1 = E2
2. E1 < E2
3. E1 > E2
4. E2 = 0 \(\neq\)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 the 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 |
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
Consider the given cell:
Pt(s) | H₂(g, 1 bar) | H⁺ (0.030 M) || Br⁻ (0.010 M) | Br₂(l) | Pt(s)
If the concentration of \(Br^-\) becomes 2 times and the concentration of \(H^+\) becomes half of the initial value, then the emf of the cell will become:
1. Two times
2. Four times
3. Eight times
4. Remains the same