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${\mathrm{SO}}_4^{2-}$ $\to$ S₂${\mathrm{O}}_3^{2-}$ + 2e

2. Cu²⁺ + 2e $\to$Cu

3. 2H₂O $\to$ O₂ + 4H⁺ + 4e

4. 2H⁺ +2e $\to$ 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