Without losing it's concentration, ZnCl₂ solution cannot be kept in contact with :

1. Au

2. Al

3. Pb

4. Ag

The standard reduction potential for Fe²⁺|Fe and Sn²⁺|Sn electrodes are -0.44 V and -0.14 V respectively. For the cell reaction,

Fe²⁺ + Sn  →  Fe + Sn²⁺, the standard Emf is - 

1. +0.30 V

2. 0.58 V

3. +0.58 V

4. -0.30 V

Three Faradays of electrical charge are passed consecutively through four separate electrolytic cells containing aqueous solutions of AgNO₃, CuSO₄, Al(NO₃)₃, and NaCl. What will be the molar ratio of the respective metals deposited at each cathode?

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?

A solution containing one mole per litre each of Cu(NO₃)₂, AgNO₃, Hg₂(NO₃)₂ and Mg(NO₃)₂ is being electrolyzed by using inert electrodes. The values of standard electrode potentials in volt (reduction potentials) are,

Ag⁺ /Ag = 0.80 V, ${\mathrm{Hg}}_2^{2+}$/2Hg = 0.79 V,

Cu²⁺/Cu = +0.34 V and Mg²⁺/Mg = -2.37 V

With increasing voltage, the sequence of deposition of metals on the cathode will be:

1. Ag, Hg, Cu, Mg

2. Mg, Cu, Hg, Ag

3. Ag, Hg, Cu

4. Cu, Hg, Ag

The change in reduction potential of a hydrogen electrode when its solution initialy at pH = 0 is neutralised to pH = 7, is a/an-

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.

A depolariser used in dry cell batteries is: 

1. Ammonium chloride 

2. Manganese dioxide

3. Potassium hydroxide 

4. Sodium phosphate

What happens to the voltage in a galvanic cell when the salt bridge is removed?

1. The voltage drops to zero.
2. The voltage remains the same.
3. The voltage gradually increases.
4. The voltage rapidly increases.

If an iron rod is dipped in CuSO₄ solution, then:

1. Blue colour of the solution turns red.

2. Brown layer is deposited on iron rod.

3. No change occurs in the colour of the solution.

4. None of the above.