Chemistry Exam Past Questions and Answers | JAMB, WAEC and NECO

Chemistry is the study of the substances that make up matter. It looks at their properties, how they react with each other, and how these reactions can create new substances.

• Question 701: The gas that will form a white precipitate with acidified silver trioxonitrate (v) is Options:
  A) NH₃
  B) SO₂
  C) CO₂
  D) HCL
  Show Answer
  The correct answer is D .
• Question 702: The correct order of increasing boiling points of the following compounds C₃H₇OH, C₇H₁₆ and C₄H₁₀ is Options:
  A) C₃H₇OH → C₄H₁₀ → C₇H₁₀
  B) C₄H₁₀ → C₇H₁₆ → C₃H₇OH
  C) C₇H₁₆ → C₃H₇OH → C₄H₁₀
  D) C₄H₁₀ → C₃H₇OH → C₇H₁₆
  Show Answer
  The correct answer is D .
• Question 703: Which of the following is NOT a true statement of the kinetic Theory of Gases? Options:
  A) The molecules move at random
  B) The size of molecules is negligble as compared with the volume of gas
  C) The molecular collisions are perfectly elastic
  D) Every molecule has the same kinetic energy at a particular temperature
  E) The average kinetic energy is proportional to the absolute temperature of the gas
  Show Answer
  The correct answer is D .
• Question 704: C_xH_Y + 4O₂ → 3CO₂ + 2H₂O. The hydrocarbon, C_xH_Y, in the reaction above is? Options:
  A) propane
  B) propene
  C) propyne
  D) propanone
  Show Answer
  The correct answer is C .
• Question 705: The decarboxylation of ethanoic acid will produce carbon (IV)oxide and Options:
  A) methane
  B) ethane
  C) propane
  D) butane
  Show Answer
  The correct answer is A .
• Question 706: Mineral acids are usually added to commercial hydrogen peroxide to Options:
  A) oxidize it
  B) decompose it
  C) minimize its decomposition
  D) reduce it to water and oxygen
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  The correct answer is C .
• Question 707: Calculate the relative molecular mass of Limestone CaCO3, (Ca = 40, C =12, O = 16) Options:
  A) 56
  B) 100
  C) 76
  D) 90
  Show Answer
  The correct answer is B .
• Question 708: An element X has electron configuration 1s² 2s² 2p⁶ 3s² 3p⁵. Which of the following statements is correct about the element? Options:
  A) lt has a completely filled p-orbital
  B) lt has 5 electrons in its outermost shell.
  C) lt belongs to group ll on the periodic table
  D) lt is a halogen
  Show Answer
  The correct answer is D .
• Question 709: Which of the following is a deliquescent compound? Options:
  A) Na₂CO₃
  B) CaCl₂
  C) CuO
  D) Na₂CO₃.10H₂O
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  The correct answer is B .
• Question 710:

  L . Evaporation. ll. Sublimation. lll. Diffusion. IV. Brownian motion.

  Which of the above can correctly be listed as evidences for the particulate nature of matter?

  Options:
  A) I and lll only
  B) ll and lV only
  C) l, ll and lll only
  D) l, ll, lll and lV
  Show Answer
  The correct answer is D .