A solution of sodium sulphate in water is electrolysed using inert electrodes. The products at the cathode and anode are respectively:
1. H2, O2
2. O2, H2
3. O2, Na
4. O2, SO2
If a salt bridge is removed from the two half cells, the voltage:
1. Drops to zero.
2. Does not change.
3. Increases gradually.
4. Increases rapidly.
Two electrolytic cells, one containing acidified ferrous chloride and another acidified ferric chloride are connected in series. The ratio of iron deposited at cathodes in the two cells when electricity is passed through the cells will be:
1. 3:1
2. 2:1
3. 1:1
4. 3:2
If the half-cell reaction A+eA- has a large negative reduction potential, it follows that:
1. A is readily reduced
2. A is readily oxidized
3. A- is readily reduced
4. A- is readily oxidized
For the reductidon of silver ions with copper metal, the standard cell potential was found to be + 0.46 V at 250C. The value of standard Gibbs energy(G0) will be ;
(F = 96500 Cmol-1)
1. -89.0 KJ
2. -89.0 J
3. -44.5 KJ
4. -98.0 KJ
A certain current liberates 0.504 g of hydrogen in 2 hr. How many gram of copper can be liberated by the same current flowing for the same time in CuSO4 solution?
1. 12.7
2. 16
3. 31.8
4. 63.5
4.5 g of aluminium (atomic mass 27u) is deposited at cathode from Al3+ solution by a certain quantity of electric charge. The volume of hydrogen produced at STP from H+ ions in solution by the same quantity of electric charge will be
1. 44.8 L
2. 22.4 L
3. 11.2 L
4. 5.6 L
On the basis of the information available from the reaction.
of O2, the minimum EMF required to carry out the electrolysis of Al2O3 is : (F=96500 C mol-1)
1. 2.14 V
2. 4.28 V
3. 6.42 V
4. 8.56 V
Cu+(aq) is unstable in solution and undergoes simultaneous oxidation and reduction according to the reaction
2Cu+(aq) Cu2+(aq) + Cu(s)
Choose the correct E0 for above reaction if E0cu2+/cu = 0.34 V and E0cu2+/cu+ = 0.15 V
1. -0.38 V
2. +4.9 V
3. +0.38 V
4. -0.19 V
The atomic mass of Al is 27. When a current of 5 faraday is passed through a solution of Al3+ ions, the mass of Al deposited is:
1. 27 g
2. 36 g
3. 45 g
4. 9 g