In the electrochemical cell:
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. From the following, which one is the relationship between E1 and E2 ?
(Given, \(\frac{RT}{F}\) = 0.059)
1.
2.
3.
4.
If the Eocell for a given reaction has a negative value, which of the following gives correct relationships for the values of ∆Go and Keq?
1.
2.
3.
4.
The number of electrons delivered at the cathode during electrolysis by a current of 1 ampere in 60 seconds is:
(Charge on electron = 1.60 × 10–19 C)
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2.
3.
4.
Consider the change in oxidation state of Bromine corresponding to different emf values as shown in the diagram below:
Then the species undergoing disproportionation is:-
1. | \(\text{BrO}^-_3\) | 2. | \(\text{BrO}^-_4\) |
3. | \(\text{Br}_2\) | 4. | \(\text{HBrO}\) |
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 |
A device that converts the energy of combustion of fuels, like hydrogen and methane, directly into electrical energy is known as:
1. | Fuel cell. | 2. | Electrolytic cell. |
3. | Dynamo. | 4. | Ni-Cd cell. |
When 0.1 mol MnO42- is oxidized the quantity of electricity required to completely oxidise MnO42-- to MnO4- is:
1. 96500 C
2. 2 x 96500 C
3. 9650 C
4. 96.50 C
The weight of silver (at.wt. = 108) displaced by a quantity of electricity which displaces 5600 mL of O2 at STP will be:
1. 5.4 g
2. 10.8 g
3. 54.0 g
4. 108.0 g
A hydrogen gas electrode is made by dipping platinum wire in a solution of HCl of pH = 10 and by passing hydrogen gas around the platinum wire at one atm pressure. The oxidation potential of the electrode would be:
1. | 0.59 V | 2. | 0.118 V |
3. | 1.18 V | 4. | 0.059 V |