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Saturday, 09 May 2026
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Chemistry Past Questions and Answers

Topic: Electrolysis

Jamb Chemistry Questions - Electrolysis

Question 51:
The pH of a solution obtained by mixing 100cm3 of a 0.2M solution of NaOH is?
  • A 1.3
  • B 7.0
  • C 9.7
  • D 12.7
View Answer & Explanation
Question 52:
The correct order of increasing oxidation number of the transition metal ions for the compounds K2Cr2O7, V2O5 and KMnO4 is
  • A V<sub style='font-size: smaller;'>2</sub>O<sub style='font-size: smaller;'>5</sub> < K<sub style='font-size: smaller;'>2</sub>Cr<sub style='font-size: smaller;'>2</sub>O<sub style='font-size: smaller;'>7</sub> < KMnO<sub style='font-size: smaller;'>4</sub>
  • B K<sub style='font-size: smaller;'>2</sub>Cr<sub style='font-size: smaller;'>2</sub>O<sub style='font-size: smaller;'>7</sub> < KMnO<sub style='font-size: smaller;'>4</sub> < V<sub style='font-size: smaller;'>2</sub>O<sub style='font-size: smaller;'>5</sub>
  • C KMnO<sub style='font-size: smaller;'>4</sub> < K<sub style='font-size: smaller;'>2</sub>Cr<sub style='font-size: smaller;'>2</sub>O<sub style='font-size: smaller;'>7</sub> < V<sub style='font-size: smaller;'>2</sub>O<sub style='font-size: smaller;'>5</sub>
  • D KMnO<sub style='font-size: smaller;'>4</sub> < V<sub style='font-size: smaller;'>2</sub>O<sub style='font-size: smaller;'>5</sub> < K<sub style='font-size: smaller;'>2</sub>Cr<sub style='font-size: smaller;'>2</sub>O<sub style='font-size: smaller;'>7</sub>
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Question 53:
What quantity of electricity will liberate 0.125 mole of oxygen molecules during the electrolysis of dilute sodium chloride solution?
[ F = 96 5000 C mol-1 ]
  • A 24 125 coulombs
  • B 48 250 coulombs
  • C 72 375 coulombs
  • D 96 500 coulombs
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Question 54:
When a current I was passed through an electrolyte solution for 40 minutes, a mass X g of a univalent metal was deposited at the cathode. What mass of the metal will be deposited when a current 2I is passed through the solution for 10 minutes?
  • A X/4 g
  • B X/2 g
  • C 2X g
  • D 4X g
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Question 55:
Which of the following statement is true of the electrochemical series?
  • A Electropositivity of metals increase down the series
  • B Electropositivity of non-metals decrease down the series
  • C Electronegativity of non-metals decrease down the series
  • D Electropositivity of metals decreases down the series
View Answer & Explanation