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

For the cell, Ti|Ti⁺(0.001M)||Cu²⁺(0.1M)|Cu,E_cell at 25$°$C is 0.83 V. E_cell can be increased:

1. By increasing [Cu²⁺]

2. By increasing [Ti⁺]

3. By decreasing [Cu²⁺]

4. None of these

The atomic mass of Al is 27. When a current of 5 faraday is passed through a solution of Al³⁺ ions, the mass of Al deposited is:

1. 27 g

2. 36 g

3. 45 g

4. 9 g

Cu⁺(aq) is unstable in solution and undergoes simultaneous oxidation and reduction according to the reaction 

2Cu⁺(aq) $\rightleftharpoons$Cu²⁺(aq) + Cu(s)

Choose the correct E0 for above reaction if E⁰_cu²⁺/cu = 0.34 V and E⁰_cu²⁺/cu+ = 0.15 V 

1. -0.38 V

2. +4.9 V

3. +0.38 V

4. -0.19 V

On the basis of the information available from the reaction.

$\frac{4}{3}\mathrm{Al} + {\mathrm{O}}_2 \stackrel{ }{\to }\frac{2}{3}{\mathrm{Al}}_2{\mathrm{O}}_3, ∆G =-827\mathrm{kJ} {\mathrm{mol}}^{-1}$ 

of O₂, the minimum EMF required to carry out the electrolysis of Al₂O₃ is : (F=96500 C mol^-1) 

1. 2.14 V

2. 4.28 V

3. 6.42 V

4. 8.56 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

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

For the reductidon of silver ions with copper metal, the standard  cell potential was found to be + 0.46 V at 25⁰C. The value of standard Gibbs energy($\Delta$G⁰⁾ will be ;
(F = 96500 Cmol^-1)

1. -89.0 KJ

2. -89.0 J

3. -44.5 KJ

4. -98.0 KJ