The standard reduction potentials of Cu2+/Cu and Cu2+/Cu+ are 0.337 and 0.153V respectively. The standard electrode potential of Cu+/Cu half cell is:
1. 0.184V
2. 0.827V
3. 0.521V
4. 0.490V
When a lead storage battery is discharged, then:
1. SO2 is evolved.
2. Lead is formed.
3. Lead sulphate is consumed.
4. Sulphuric acid is consumed.
The molar conductances of Ba2+ and Cl- 127 and 76Ω-1 cm-1 mol-1 respectively at infinite dilution. The equivalent conductance of BaCl2 at infinite dilution will be
1. 139.52
2. 203
3. 279
4. 101.5
A depolariser used in dry cell batteries is:
1. Ammonium chloride
2. Manganese dioxide
3. Potassium hydroxide
4. Sodium phosphate
The reaction taking place at anode when an aqueous solution of CuSO4 is electrolysed using inert Pt electrode:
1. 2 S2 + 2e
2. Cu2+ + 2e Cu
3. 2H2O O2 + 4H+ + 4e
4. 2H+ +2e H2
An increase in equivalent conductance of a strong electrolyte with dilution is mainly due to
1. increase in ionic mobility of ions
2. 100% ionisation of electrolyte at normal dilution
3. increase in both, i.e. number of ions and ionic mobility of ions
4. increase in number of ions
A hydrogen gas electrode is made by dipping platinum wire in a solution of HCI of pH = 10 and by passing hydrogen gas around the platinum wire at 1 atm pressure. The oxidation potential of the electrode would be:
1. 0.059 V
2. 0.59 V
3. 00.118 V
4. 1.18 V
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
Which one of the following pairs of substances on reaction will not evolve H2 gas?
1. Iron and H2SO4 (aq)
2. iron and steam
3. Copper and HCl(aq)
4. Sodium and ethyl alcohol
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