H2O2 is
a catalyst
An oxidizing agent
A reducing agent
Both '2' and '3'
Calculate the e.m.f. of a galvanic cell, the cell reaction is Mg(s) + Cu2+(aq) → Cu(s) + Mg2+(aq). If the standard reduction potentials of Mg and Cu are -2.37 V and + 0.34 V?
+ 2.03 V
- 2.03 V
+ 2.71 V
- 2.71 V
0.0352
0.0591
0.1183
0.2366
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
The mass of copper deposited from a solution of CuSO4 by passing a current of 5 A for 15 min is (Atomic Wt. of copper = 63.5)
0.3 g
0.5 g
0.7 g
0.9 g
If 0.25 g of copper is deposited by a current of 0.2 ampere in 10 minutes, then the electrochemical equivalent of the copper is
0.2
0.02
0.002
0.0002
2H2(g) + O2(g) → 2H2O(I)
2Fe(s) + O2(g) + 4H+(aq) → 2Fe2+(aq) + 2H2O(I)
Pb(s) + PbO2(s) + 2H2SO4(aq) →2PbSO4(s) + 2H2O(I)
Cd(s) + 2Ni(OH)3(s) → CdO(s) + 2Ni(OH)2(s) + H2O(I)
In which cell, free energy of a chemical reaction is directly converted into electricity?
Fuel cell
Leclanche cell
Concentration cell
Lead storage cell
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?
The mass of copper deposited from a solution of Cu2S by passing a current of 2.5 ampere for 6 minute is
