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Saturday, 13 June 2026
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Chemistry Past Questions and Answers

Jamb 2008 Chemistry Questions

Question 26:
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
Question 27:
NH3(g) + HCl(s) → NH4Cl(s)
The entropy change in the system above is
  • A Positive
  • B Zero
  • C Negative
  • D Indeterminate
View Answer & Explanation
Question 28:
Which of the following reaction is endothermic?
  • A C<sub style='font-size: smaller;'>(s)</sub> + O<sub style='font-size: smaller;'>2(g)</sub> → CO<sub style='font-size: smaller;'>2(g)</sub>
  • B CaO<sub style='font-size: smaller;'>(s)</sub> + H<sub style='font-size: smaller;'>2</sub>O<sub style='font-size: smaller;'>(l)</sub> → Ca(OH)<sub style='font-size: smaller;'>2(s)</sub>
  • C C<sub style='font-size: smaller;'>(s)</sub> + H<sub style='font-size: smaller;'>2</sub>O<sub style='font-size: smaller;'>(g)</sub> → CO<sub style='font-size: smaller;'>(g)</sub> + H<sub style='font-size: smaller;'>2(g)</sub>
  • D HCl<sub style='font-size: smaller;'>(aq)</sub> + NaOH<sub style='font-size: smaller;'>(aq)</sub> → NaCl<sub style='font-size: smaller;'>(aq)</sub> + H<sub style='font-size: smaller;'>2</sub>O<sub style='font-size: smaller;'>(l)</sub>
View Answer & Explanation
Question 29:
A catalyst speeds up the rate of chemical reaction by
  • A Taking part in the reaction
  • B Increasing the activation energy of the reaction
  • C Lowering the activation energy of the reaction
  • D Increasing the heat content
View Answer & Explanation
Question 30:
The rate of a reaction usually decrease in the concentration of reactants because
  • A Kinetic energy decrease
  • B Temperature increase
  • C Speed increases
  • D Reactants collision decrease
View Answer & Explanation