JAMB Chemistry questions: Electrolysis

22 questions with answers and explanations. Tap an option to check yourself.

1. Question 1· Electrolysis· JAMB

   How much charge is needed to deposit 1 mole of aluminium from Al³⁺ ions? (F = 96 500 C/mol)

   • A96 500 C
   • B289 500 C
   • C193 000 C
   • D32 167 C

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   Explanation and discussion

2. Question 2· Electrolysis· JAMB

   When a spoon is electroplated with silver, the spoon is made the

   • Acathode
   • Banode
   • Celectrolyte
   • Dsalt bridge

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3. Question 3· Electrolysis· JAMB

   Oxidation always takes place at the

   • Aanode
   • Bcathode
   • Csalt bridge
   • Delectrolyte surface

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   Explanation and discussion

4. Question 4· Electrolysis· JAMB

   During the electrolysis of dilute sulphuric acid with platinum electrodes, the gas liberated at the cathode is:

   • Ahydrogen
   • Boxygen
   • Csulphur(IV) oxide
   • Dchlorine

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5. Question 5· Electrolysis· JAMB

   An electrolyte is a compound that

   • Aconducts electricity when molten or in solution and is decomposed by it
   • Bconducts electricity as a solid without change
   • Cnever conducts electricity
   • Dis always a metal

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6. Question 6· Electrolysis· JAMB

   Faraday's second law of electrolysis states that, for the same quantity of electricity, the masses of different substances liberated are proportional to their

   • Aequivalent masses (molar mass ÷ charge on the ion)
   • Bdensities
   • Catomic numbers
   • Dvolumes

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7. Question 7· Electrolysis· JAMB

   In the electrolysis of concentrated sodium chloride solution (brine), the gas given off at the anode is

   • Achlorine
   • Boxygen
   • Chydrogen
   • Dsodium vapour

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8. Question 8· Electrolysis· JAMB

   What mass of copper is deposited by 0.2 faraday of electricity from Cu²⁺ ions? (Cu = 64)

   • A64 g
   • B12.8 g
   • C3.2 g
   • D6.4 g

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9. Question 9· Electrolysis· JAMB

   In the electrolytic refining of copper, pure copper is deposited on the

   • Acontainer walls
   • Banode
   • Celectrolyte surface
   • Dcathode

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10. Question 10· Electrolysis· JAMB

    When dilute tetraoxosulphate(VI) acid is electrolysed with platinum electrodes, the products are

    • Ahydrogen at the cathode and oxygen at the anode
    • Boxygen at the cathode and hydrogen at the anode
    • Csulphur at the anode
    • Dsulphur(IV) oxide at the cathode

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11. Question 11· Electrolysis· JAMB

    Which of the following is commonly used as an inert electrode?

    • Airon
    • Bcopper
    • Czinc
    • Dgraphite

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12. Question 12· Electrolysis· JAMB

    How many moles of silver are deposited by 9650 C of electricity from Ag⁺ ions? (F = 96 500 C/mol)

    • A0.1 mol
    • B1 mol
    • C0.01 mol
    • D0.05 mol

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13. Question 13· Electrolysis· JAMB

    The electrolysis of brine produces

    • Ahydrogen and oxygen only
    • Bsodium and oxygen
    • Cchlorine and sodium metal only
    • Dchlorine, hydrogen and sodium hydroxide

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14. Question 14· Electrolysis· JAMB

    In the electrolysis of acidified water, the ratio of the volume of hydrogen to oxygen produced is

    • A2 : 1
    • B1 : 2
    • C1 : 1
    • D4 : 1

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15. Question 15· Electrolysis· JAMB

    In the electrolysis of molten lead(II) bromide, the products are

    • Alead at both electrodes
    • Bbromine at the cathode and lead at the anode
    • Chydrogen and oxygen
    • Dlead at the cathode and bromine at the anode

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16. Question 16· Electrolysis· JAMB

    A current of 2 A flows for 965 s through a solution of a divalent metal salt. The amount of metal deposited is: (F = 96 500 C/mol)

    • A0.005 mol
    • B0.02 mol
    • C0.01 mol
    • D0.1 mol

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17. Question 17· Electrolysis· JAMB

    In the electrolysis of dilute sodium chloride solution with inert electrodes, the gas mainly given off at the anode is

    • Asodium
    • Bchlorine
    • Chydrogen
    • Doxygen

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18. Question 18· Electrolysis· JAMB

    What quantity of electricity deposits 6.4 g of copper from Cu²⁺ ions? [Cu = 64, F = 96,500 C]

    • A19,300 C
    • B9,650 C
    • C96,500 C
    • D38,600 C

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19. Question 19· Electrolysis· JAMB

    During electrolysis, positive ions (cations) move towards the

    • Aelectrolyte surface
    • Banode
    • Ccathode
    • Dsalt bridge

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20. Question 20· Electrolysis· JAMB

    In the purification of copper by electrolysis, the impure copper is made the

    • Aanode
    • Bcathode
    • Celectrolyte
    • Dsalt bridge

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    Explanation and discussion