CHEMISTRY

JAMB 2000 - Question 26

Chemistry 2000 JAMB Past Questions - Question 26: (1/2)Zn²+(aq) + e−  → (1/2)Zn(s) In the reaction above, calculate the quantity of electricity required to discharge zinc.  [F= 96,500 C mol−¹]

Choose the correct answers from the options given.
(1/2)Zn²+(aq) + e−  → (1/2)Zn(s) In the reaction above, calculate the quantity of electricity required to discharge zinc.  [F= 96,500 C mol−¹]
A:
B:
C:
D:
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Correct Answer

C

Explanation

The quantity of electricity required to discharge zinc can be calculated using Faraday's law of electrolysis, which states that the amount of substance produced at an electrode is directly proportional to the quantity of electricity passed through the cell.

The equation you provided represents the reduction of Zn^2+ to Zn. The molar quantity of electricity required can be calculated using the equation:

Quantity of electricity (Q) = nF

Where:
n = number of moles of electrons transferred in the balanced chemical equation
F = Faraday's constant (96,485 C/mol)

In this case, since the balanced chemical equation involves the transfer of 2 moles of electrons, the quantity of electricity required can be calculated as:

Q = 2 mol × 96,485 C/mol = 192,970 C

So, the quantity of electricity required to discharge one mole of zinc is 192,970 C.