the standard emf of the reaction Fe + 2Fe3+ 3Fe2+ will be.
0.111 V
0.330 V
1.653 V
1.212 V
On the basis of the following Eovalues, the strongest oxidising agent is.
[Fe(CN)6]4-
Fe2+
Fe3+
[Fe(CN)6]3
Which one of the following pairs of substances on reaction will not evolve H2 gas.
Iron and H2SO4 (aqueous).
Iron and steam.
Copper and HCI (aqueous).
Sodium and ethyl alcohol.
AI2o3 is reduced by electrolysis at low potentials and high currents. If 4.0 x 104 A of current is passed through molten AI2O3for 6 h, what mass of aluminium is produced ? (Assume 100% current efficiency, at mass of AI = 27 g mol-1)
9.0 x 103g
8.1 x 104g
2.4 x 105g
1.3 x 104g
The equivalent conductance of solution of a weak monobasic acid is 8.0 mho cm2 and at infinite dilution is 400 mho cm2.
1.25 x 10-5
1.25 x 10-6
6.25 x 10-4
1.25 x 10-4
The equivalent conductances of Ba2+ and Cl- are 127 and 76 ohm-1 cm-1 eq-1 respectively at infinite dilution. The equivalent conductance of BaCI2 at infinite dilution will be.
139.52
203
279
101.5
A 5 A current is passed through a solution of zinc sulphate for 40 min. The amount of zinc deposited at the cathode is.
40.65 g
0.4065g
4.065g
65.04g
The efficiency of a fuel cell is given by.
The standard emf of a galvanic cell involving cell reaction with n = 2 is found to be 0.295 V at 25o C. The equilibrium constant of the reaction would be.
(Given F = 96500 C mol-1; R =8.314 JK-1 mol-1)
2.0 x1011
4.0 x 1012
1.0 x 102
1.0 x 1010
Eo for the cell, Zn [Zn2+ (aq)] [Cu2+(aq)] Cu is 1.10 V at 25oC. The equilibrium constant for the reaction,
10-37
10-28
10-18
10-17
