MCQs on Electrochemistry

Electrochemistry is concerned with charges and with their movement and transfer from one medium to another. The ultimate unit of charge is that carried by the electron, electrons are important in electrochemistry and their functions here are similar to some of those which they exhibit in related disciplines more usually regarded as the province of physics. The science of thermionics is built on the exchange of electrons between a solid and a vacuum; that of transistor electronics is based on their transfer between one solid phase and another.

1. The aqueous solution of which of the following compounds is the best conductor of electric current?

1. Acetic acid,
2. Hydrochloric acid
3. Ammonia
4. Fructose

Answer: (b)

2. An increase in the conductivity equivalent of a solid electrolyte with dilution is primarily due to

1. increased ionic mobility of ions
2. 100 percent electrolyte ionisation with natural dilution
3. increase in both ion numbers and ionic mobility
4. A rise in ion counts

Answer: (a)

3. The equivalent conductance of Ba²⁺ and Cl^– are respectively 127 and 76 ohm^-1 cm^-1 eq^-1 at infinite dilution. The equivalent conductance of BaCl₂ at infinite dilution will be

1. 139.5
2. 203
3. 279
4. 101.5

Answer: (a)

4. When heating one end of a metal plate, the other end gets hot because of

1. the resistance of the metal
2. mobility of atoms in the metal
3. energised electrons moving to the other end
4. minor perturbation in the energy of atoms.

Answer: (c)

5. The weight of silver displaced by a quantity of electricity which displaces 5600ml of O₂ at STP will be

1. 5.4g
2. 10.8g
3. 54.9g
4. 108.0g

Answer: (d)

6. Once a current of 1.0 ampere was passed through one litre of CuCl₂ solution for 16 min and 5 sec, all of the solution’s copper was deposited at the cathode. The strength of solution CuCl₂ was (Molar mass of Cu = 63.5; Faraday constant = 96,500 C/mol)

1. 0.01N
2. 0.01M
3. 0.02M
4. 0.2N

Answer: (a)

7. On electrolysis of dilute sulphuric acid using platinum electrodes, the product obtained at the anode will be

1. hydrogen
2. oxygen
3. hydrogen sulphide
4. sulphur dioxide

Answer: (b)

8. A device that converts the energy of combustion of fields like hydrogen and methane directly into electrical energy is known as

1. Electrolytic cell
2. Dynamo
3. Ni-Cd cell
4. Fuel cell

Answer: (d)

9. Which reaction is not feasible?

1. 2KO + Br₂ → 2KBr + I₂
2. 2KBr + I₂ → 2KI + Br₂
3. 2KBr + Cl₂ → 2KCl + Br₂
4. 2H₂O + 2F₂ → 4HF + O₂

Answer: (b)

10. Without losing its concentration ZnCl₂ solution cannot be kept in contact with

1. Au
2. Al
3. Pb
4. Ag

Answer: (b)