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Thursday, 05 November 2026
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Chemistry Past Questions and Answers

Jamb 2008 Chemistry Questions

Question 21:
Insoluble salts can be prepared by
  • A Titrating an alkali against an appropriate acid
  • B Reacting an acid with trioxocarbonatr (IV) salt
  • C Directing combination of the elements which make up the salt
  • D Mixing two soluble compounds containing the metallic radical and the acidic radical
View Answer & Explanation
Question 22:
The oxidation state of carbon in HCOOH is
  • A -1
  • B +2
  • C +3
  • D Zero
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Question 23:
What is the IUPAC nomenclature of the compound NaCIO?
  • A Sodium oxochlorate (I)
  • B Sodium chloro (I) oxide
  • C Sodium monooxochlorate (II)
  • D Sodium chloro (I) monoxide
View Answer & Explanation
Question 24:
In recharging a lead-acid accumulator, the reaction at the cathode can be represented as
  • A Pb<sup style='font-size: smaller;'>2+</sup><sub style='font-size: smaller;'>(aq)</sub> + SO<sup style='font-size: smaller;'>2-</sup><sub style='font-size: smaller;'>4(aq)</sub> →PbSO<sub style='font-size: smaller;'>4(s)</sub>
  • B Pb<sup style='font-size: smaller;'>2+</sup><sub style='font-size: smaller;'>(aq)</sub> + 2e<sup style='font-size: smaller;'>-</sup> →Pb<sub style='font-size: smaller;'>(s)</sub>
  • C Pb<sup style='font-size: smaller;'>2+</sup><sub style='font-size: smaller;'>(aq)</sub> + 2H<sub style='font-size: smaller;'>2</sub>O<sub style='font-size: smaller;'>(l)</sub> → PbO<sub style='font-size: smaller;'>2(s)</sub> + 4H<sup style='font-size: smaller;'>+</sup><sub style='font-size: smaller;'>(aq)</sub> + 4e<sup style='font-size: smaller;'>-</sup>
  • D Pb<sub style='font-size: smaller;'>(s)</sub> → Pb<sup style='font-size: smaller;'>2+</sup><sub style='font-size: smaller;'>(aq)</sub> + 2e<sup style='font-size: smaller;'>-</sup>
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Question 25:
If a given quantity of electricity liberates 0.65g of Zn2+, what amount of Hg2+ would be liberated by the same quantity of current?
[Zn = 65, Hg = 201]
  • A 1.00g
  • B 2.10g
  • C 4.02g
  • D 8.04g
View Answer & Explanation