The specific conductance of a 0.1 M KCl solution at 23 °C is 0.012 Ω-1 cm-1 . The resistance of cells containing the solution at the same temperature was found to be 55 Ω. The cell constant will be:
1. | 0.142cm-1 | 2. | 0.66 cm-1 |
3. | 0.918 cm-1 | 4. | 1.12cm-1 |
Given below are the half-cell reactions,
Mn2+ + 2e-
Mn will be:
E0 for Fe2+ + 2e → Fe is -0.44 volt and E0 for Zn2+ + 2e→ Zn is -0.76 volt, thus:
1. Zn is more electropositive than Fe
2. Fe is more electropositive than Zn
3. Zn is more electronegative
4. none of the above
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.
A 5A current is passed through a solution of copper sulphate for 40 min. The amount of copper deposited at the cathode is
1. 40.65g
2. 0.45g
3. 3.94g
4. 65.04g
, the standard emf of the reaction
will be
1. 0.111V
2. 0.330V
3. 1.653V
4. 1.212V
The standard electrode potential for Sn4+/Sn2+ couple is +0.15 V and that for the Cr3+/Cr couple is -0.74 V. These two couples in their standard state are connected to make a cell. The cell potential will be:
1. | +0.89 V | 2. | +0.18 V |
3. | +1.83 V | 4. | +1.199 V |
If an iron rod is dipped in CuSO4 solution, then:
1. Blue colour of the solution turns red.
2. Brown layer is deposited on iron rod.
3. No change occurs in the colour of the solution.
4. None of the above.
Without losing it's concentration, ZnCl2 solution cannot be kept in contact with :
1. Au
2. Al
3. Pb
4. Ag
Al2O3 is reduced by electrolysis at low potentials and high currents. If 4.0 x 104 A of current is passed through molten Al2O3 for 6 h, what mass of aluminium is produced? (Assume 100% current efficiency, atomic mass of Al = 27g mol-1)
1. 9.0 x 103 g
2. 8.1 x 104 g
3. 2.4 x 105 g
4. 1.3 x 104 g