Electrolysis of aqueous solution of \(CuSO_4\) is carried out, where 300 mg of copper is deposited (atomic mass of Cu = 63.54). After this 600 milli amp. current is further passed for 28 minutes. Calculate total volume of \(O_2\) released (in ml), given that 1 mole of a gas occupy 22.4 litres.

Given half reactions:
\(\mathrm{Cu}^{+2}(\mathrm{aq})+2 \mathrm{e}^{-} \longrightarrow \mathrm{Cu}(\mathrm{~s})\)
\(2 \mathrm{H}_2\mathrm{O}(l) \longrightarrow \mathrm{O}_2(\mathrm{~g})+4 \mathrm{H}^{+}(\mathrm{aq})+4 \mathrm{e}^{-}\)

1. 110
2. 111.15
3. 101.5
4. 80.5
Subtopic:  Electrode & Electrode Potential | Faraday’s Law of Electrolysis |
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If one coulomb of electric charge is passed through a solution of silver nitrate (\(\mathrm{AgNO}_3\)) during electrolysis, what is the mass of silver (in milligrams) deposited at the electrode?
(Given: Molar mass of Ag = 108 g/mol)
1. 1.12 mg  2. 3.26 mg
3. 2.54 mg 4. 4.02 mg
Subtopic:  Faraday’s Law of Electrolysis |
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If one Faraday of electricity is used in the discharging of \(\text{Cu}^{2+},\) then find the mass (in g) of Cu deposited (In nearest integer):

1. 32
2. 19
3. 90
4. 78
Subtopic:  Faraday’s Law of Electrolysis |
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In the aqueous solution of \([\text{AuCl}_4]^-\), the current is passed for 10 minutes during the electrolysis, the mass Au deposited at Cathode is 1.97 gm. Find out current required (in A): (Nearest integer)

1. 6 
2. 5 
3. 1 
4. 9
Subtopic:  Faraday’s Law of Electrolysis |
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What is the mass of\(\text { Zn }\)(in mg) is deposited when a current of \(0.015~\text{A}\) was passed for \(15\) minutes through a \(\mathrm{ZnSO}_4\) solution.
[In nearest integer]
[Given: Atomic weight of \(\text {Zn }=65.4\) ]

1. Seven (7)
2. Eight (8)
3. Ten (10)
4. Five (5)
Subtopic:  Faraday’s Law of Electrolysis |
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How many moles of electrons are required to reduce 1 mole of permanganate ions into manganese dioxide?

1. 3
2. 6
3. 4
4. 7
Subtopic:  Faraday’s Law of Electrolysis |
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How many charges in Faraday is required in the conversion of 1 mole \(Cr_2O_7^{2-}\) into \(Cr^{3+} \)?

1. 3 
2. 6
3. 4 
4. 2
Subtopic:  Faraday’s Law of Electrolysis |
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Electrolysis of Fe₂(SO₄)₃ solution is carried out for 'x' minutes with a current of 1.5 A, depositing 0.3482 g of Fe. What is the value of x to the nearest integer?
[Given: \(1 ~\text{F}=96500 ~\text{C} ~\text{mol}^{-1}\)
Atomic mass of \(\text{Fe}=56~ \text{g}~ \text{mol}^{-1}\)]
1. 20
2. 25
3. 18
4. 17
Subtopic:  Faraday’s Law of Electrolysis |
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A solution of Ni(NO3)2 is electrolysed between platinum electrodes using 0.1 Faraday electricity. The number of moles of Ni that will be deposited at the cathode are:

1. 0.10 2. 0.05
3. 0.20 4. 0.15
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Aluminium oxide may be electrolysed at 1000 °C to furnish aluminium metal.
The cathode reaction is  Al3+ + 3e- → Al.
To prepare 5.12 kg of aluminium metal by this method would require:
(Atomic mass = 27 amu; 1 faraday=96,500 Coulombs)

1. 5.49×101 C of electricity
2. 5.49×104 C of electricity
3. 1.83×107 C of electricity
4. 5.49×107 C of electricity

Subtopic:  Faraday’s Law of Electrolysis |
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