Faraday's second law

Q.

Salts of A (atomic mass 15), B (atomic mass 27) and C (atomic mass 48) were electrolyzed using the same amount of charge. It was found that when 4.5 g of A was deposited, the masses of B and C deposited were 2.7 g and 9.6 g. The valences of A, B and C were respectively

1. 1, 3 and 2
2. 3, 1 and 3
3. 3, 1 and 2
4. 2, 3 and 2

Q.

In electrolytic reduction of a nitroarene with 50% current efficiency, 20.50 g of the compound is reduced by $2\times 96500$ C of electric charge. The molar mass of the compound is :

1. 20.50 g

2. 10.25 g

3. 123.00 g

4. 61.50 g

Q.

When aq. AgNO₃ is electrolysed using Pt electrodes if 3.2 g of O₂ is liberated at the anode, the amount Ag that will be deposited at the cathode in grams is (at wt. of Ag = 108)

1. 43.2 g

2. 32 g

3. 1.6 g

4. 4.32 g

Q. The recovery of silver from the solutions used in developing and fixing photographic film and prints present just such a problem. Silver is an expensive metal, and the recovery is profitable. Moreover, if not recovered, the silver ions would constitute and undesirable pollutant in water supplies. What is undesirable pollutant?

1. $AgBr$
2. $AgCl$
3. $A{g}_{2}S$
4. $A{g}_{2}O$

Q.

When 9.65 coulombs of electricity is passed through a solution of silver nitrate

(atomic weight of taking as 108) the amount of silver deposited is

[EAMCET 1992; KCET 2000]

1. 10.8 mg
2. 5.4 mg
3. 16.2 mg
4. 21.2 mg

Q.

What current strength would be required to produce hydrogen gas at the rate of $1.12c{m}^3{s}^{-1}$(STP) by the electrolysis of aqueous NaCl solution with 96.5% current efficiency ?

1. 10.00 A

2. 0.10 A

3. 9.65 A

4. 9.31 A

Q. How many coulombs are required for the oxidation of 1 mol of $H_2{O}_2$ to $O_2?$

1. 9.65 × 10⁴ C
2. 1.93 × 10⁵ C
3. 19.3 × 10² C
4. 93000 C