The Zn acts as sacrificial or cathodic protection to prevent rusting of iron because:

1. $E_{OP}^{\circ }$ of Zn < $E_{OP}^{\circ }$ of Fe

2. $E_{OP}^{\circ }$ of Zn > $E_{OP}^{\circ }$ of Fe

3. $E_{OP}^{\circ }$ of Zn = $E_{OP}^{\circ }$ of fe

4. Zn is cheaper than iron

What mass of copper will be deposited by passing 2 faraday of electricity through a solution of Cu(II) salt?

1. 35.6 g

2. 63.5 g

3. 6.35 g

4. 3.56 g

The same amount of electricity was passed through two cells containing molten Al₂O₃ and molten NaCl. If 1.8 g of Al were liberated in one cell, the amount of Na liberated in the other cell is:

1. 4.6 g

2. 2.3 g

3. 6.4 g

4. 3.2 g

The standard reduction electrode potentials of three metals X, Y, and Z are given as -1.2 V, +0.5 V, and -3.0 V, respectively. Based on these values, what is the correct order of their reducing power?

During an electrolysis experiment, if a 100 mA current is passed through a solution of AgNO₃ for 30 minutes, how many coulombs of electricity will be consumed?

1. 108 C

2. 18000 C

3. 180 C

4. 3000 C

Standard reduction potentials at 25$°$C of Li⁺/Li, Ba²⁺/Ba, Na⁺/Na and Mg²⁺/Mg are -3.05, -2.90, -2.71 and -2.37 V respectively. Which one of the following is the strongest oxidising agent ?

1. Mg²⁺

2. Ba²⁺

3. Na⁺

4. Li⁺

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

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

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

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