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Friday, 08 May 2026
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Chemistry Past Questions and Answers

Topic: Electrolysis

Jamb Chemistry Questions - Electrolysis

Question 26:
In the electrolysis of aqueous solution of K2SO 4 in the above cell, which species migrate to the anode?
  • A SO<sup style='font-size: smaller;'>2-</sup>OH <sup style='font-size: smaller;'>-</sup>
  • B K <sup style='font-size: smaller;'>+</sup> and SO <sub style='font-size: smaller;'>4</sub><sup style='font-size: smaller;'>2-</sup>
  • C OH and HO
  • D H<sub style='font-size: smaller;'>3</sub>O <sup style='font-size: smaller;'>+</sup> and K
View Answer & Explanation
Question 27:
Complete oxidation of propan -1- ol gives?
  • A Propanal
  • B Propan-2-al
  • C Propan-1-one
  • D Propanoic acid
View Answer & Explanation
Question 28:
Which of the following reactions takes place in the cathode compartment during the electrolysis of copper (II) chloride solution?
  • A Cu<sup style='font-size: smaller;'>2+</sup> + 2e<sup style='font-size: smaller;'>-</sup> → Cu(s)
  • B 2Cl<sup style='font-size: smaller;'>-</sup> -2e → Cl<sub style='font-size: smaller;'>2</sub>
  • C Cu<sub style='font-size: smaller;'>(s)</sub> -2e → Cu<sup style='font-size: smaller;'>2+</sup><sub style='font-size: smaller;'>(aq)</sub>
  • D Cu<sup style='font-size: smaller;'>2+</sup><sub style='font-size: smaller;'>(aq)</sub> + 2Cl<sup style='font-size: smaller;'>-</sup><sub style='font-size: smaller;'>(aq)</sub> → CuCl<sub style='font-size: smaller;'>2(aq)</sub>
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Question 29:
Crude copper can be purified by the electrolysis of CuSO4(aq) if?
  • A Platinum electrodes are used
  • B The crude copper is made the anode of the cell
  • C The crude copper is made the cathode of the cell
  • D Crude copper electrodes are used
View Answer & Explanation
Question 30:
Use the graph above to answer this question. The mass of a substance, M, liberated at an electrode during electrolysis is proportional to the quantity of electricity, Q passing through the electrolyte. This is represented graphically by.
  • A A
  • B B
  • C C
  • D D
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