In the reaction : 14 H+ + Cr2O72- + 3Ni → 2Cr3+ + 7H2O + 3Ni2+, which of the following substance is a reducing agent?
H2O
Ni
H+
Cr2O72-
The mass of copper deposited from a solution of Cu2S by passing a current of 2.5 ampere for 6 minute is
0.3 g
0.5 g
0.7 g
0.9 g
If emf of the cell Zn| Zn2 (0.01 M)| | Fe2+ (0.001 M) | Fe at 298 K is 0.2957, then the value of equilibrium constant for the cell reaction is?
Which of the following is the strongest oxidizing agent?
BrO3-/Br2+ ; Eo = + 1.50
Fe3+/Fe2+ ; Eo = + 0.76
MnO4-/Mn2+ ; Eo = + 1.52
Cr2O72-/Cr3+ ; Eo = + 1.33
0.0352
0.0591
0.1183
0.2366
In which cell, free energy of a chemical reaction is directly converted into electricity?
Fuel cell
Leclanche cell
Concentration cell
Lead storage cell
Which of the following reaction does not involve either in oxidation or reduction?
Cr → CrCl3
Na → Na+
2S2O32- → S4O62-
K2CrO4 → K2CrO7
The standard e.m.f of a cell, involving one electron change is 0.591 V 25oC. The equilibrium constant of the reaction is (F = 96500 C-mol-1; R = 8.314 J - K-1 - mol-1)
1.0 × 101
1.0 ×105
1.0 ×1010
1.0 ×1030
Among the properties (a) reducing (b) oxidizing (c) complexing the set of properties shown by CN- ion towards metal species is
a, b
a, c
b, c
a, b, c
In the reaction : Ag2O + H2O2 → 2Ag + H2O + O2, the H2O2 acts as
Reducing agent
Oxidizing agent
Bleaching agent
None of these
