The electrode potentials of half-cell reactions are: Zn → Zn2+ + 2e- ; E = -0.76 V and Fe → Fe2+ + 2e- ;E = 0.41 V. The e.m.f of cell Fe2+ + Zn →Zn2+ + Fe is
+ 1.17 V
+ 0.35 V
- 1.17 V
- 0.35 V
When 1 Faraday current is passed, which of the following would deposit 1g atomic weight of the metal?
NaCl
BaCl2
AlCl3
CuSO4
The standard free energy change for the reaction, 2Ag + 2H+ → H2 + 2Ag+ is (EoAg+ = -0.80 V and F = 96500 C-mol-1
+ 154.4 kJ
-154.4 kJ
+308.8 kJ
-308.8 kJ
A certain current liberates 0.504g of hydrogen in 2 hours. The copper liberated by the same current flowing for the same time in copper sulphate solution will be
12.7 g
16.0 g
31.8 g
63.5 g
The charge on one electron is (Avogadro's number = 6.023 × 1023)
1 × 10-19 C
1.6 × 10-19 C
2.6 × 10-19 C
3.6 × 10-19 C
The charge required to liberate 112 ml of hydrogen from acidified water is
0.1 F
2 F
965 C
96500 C
Which of the following is the strongest oxidising agent?
BrO3-/Br2+ ; Eo = + 1.50
Fe3+/Fe2+ ; Eo = + 0.76
MnO4-/Mn2+ ; Eo = + 1.52
Cr2O72-/Cr3+ ; Eo = + 1.33
Faraday constant
is a numerical constant
depends on equivalent
depends upon the current passed
depends on the number of electrons
The oxidation number of oxygen atom in O22- ion is
- 1
-2
-3
-5
The oxidation number of As in H2AsO4- is
6
7
5
9