ABC-OBJ CHEM - PRACTICE EXERCISE 17b

According to Faraday’s second law of electrolysis when the same quantity of electricity is passed through different electrolytes, the amounts of different substances produced at the electrodes are directly proportional to their :

• atomic weights

• molecular weights

• atomic numbers

• equivalent weights.

The quantity of electricity needed to liberate 0.1 gram equivalent of an element at the electrode is :

• 9650 Faraday

• 96500 C

• 9650 C

• 96500 Faraday

When an aqueous solution of sulphuric acid is electrolysed, the ion discharged at the anode is :

• Hydrogen

• Hydroxyl

• Sulphate

• Oxygen.

One Faraday of electricity will liberate one gram atom of metal from a solution of

• AuCl₃

• BaCl₂

• CuSO₄

• KCl.

Two electrolytic cells, one containing acidified ferrous sulphate and other containing acidified ferric sulphate are connected in series. The ratio of iron deposited at cathodes in the two cells will be respectively

• 2 : 1

• 2 : 3

• 1 : 1

• 3 : 2.

What weight of copper will be deposited by passing 2 Faradays of electricity through a cupric salt (At. mass = 63.5) ?

• 63.5 g

• 31.75 g

• 127 g

• 2.0 g.

How many coulombs of electricity are consumed when a 100 mA current is passed through a solution of AgNO3 for half an hour during an electrolysis experiment ?

• 108

• 18000

• 180

• 3000.

How many Faradays are required to liberate 8 g of hydrogen?

• 2

• 4

• 8

• 16.

What weight of copper will be deposited by passing 2 Faradays of electricity through a cupric salt (At .wt. of Cu = 63.5) ?

• 2.0 g

• 3.175 g

• 63.5 g

• 127.0 g.

How many coulombs of electricity are required for the oxidation of 1 mole of H₂O to O₂ ?

• 9.65 × 10⁴ C

• 4.825 × 10⁵ C

• 1.93 × 10⁵ C

• 1.93 × 10⁴ C.

Answer explanation