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Wednesday, 20 May 2026
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Chemistry Past Questions and Answers

Jamb 1979 Chemistry Questions

Question 46:
A piece of metal (M) is dissolved in nitric acid and the resulting solution is treated with a small quantity of sodium hydroxide to produce a white precipitate (B) which redissolves on the addition of excess alkali. The precipitate (B)when ignited in a crucible produces the oxide of the metal(m). The METAL M is
  • A Zn
  • B Cu
  • C Al
  • D Au
  • E Ca
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Question 47:
Pick out the correct statement
  • A Zin heated to redness reacts with steam to give oxygen and zinc oxide
  • B Zinc heated to redness reacts with steam to give oxygen and hydrogen
  • C Zinc does not react with hot or cold water
  • D Zinc reacts with hot water to form zinc oxide and hydrogen
  • E Zinc reacts very easily with cold water to give zinc oxide and hydrogen
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Question 48:
Consider the following exothermic reaction 2SO2(g) + O2(g) = 2SO3 (g) . If the temperature of the reaction is reduced from 800oC to 500oC, and no other change takes place, then
  • A The reaction rate increases
  • B Concentration of SO<sub style='font-size: smaller;'>3</sub> decreases
  • C Concentration of SO<sub style='font-size: smaller;'>3</sub> increases
  • D SO<sub style='font-size: smaller;'>2</sub> gas becomes unreactive
  • E O<sub style='font-size: smaller;'>2</sub> gas becomes unreactive
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Question 49:
The IUPAC name for
  • A 2-methylbut-3-ene
  • B 2-methylbut-4-ene
  • C 3-methylbut-2-ene
  • D 3-methylbut-1-ene
  • E 3-methylpent-1-ene
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