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 121: The bond which joins two ethanoic acid molecules in the liquid state is Options:
  A) a covalent bond
  B) an ionic bond
  C) a dative covalent bond
  D) a hydrogen bond
  Show Answer
  The correct answer is D .
• Question 122:

  What is the IUPAC name for the compound CCl${}_4$?

  Options:
  A) Tetrahydrochloride
  B) Tetrachloromethane
  C) Carbon tetrachloride
  D) Chloroform
  Show Answer
  The correct answer is B .
• Question 123:

  

  The IUPAC name for

  Options:
  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
  Show Answer
  The correct answer is D .
• Question 124: Alkanols have the general molecular formula Options:
  A) C₁H_2n-2
  B) C₁H_2n-1CHO
  C) C₁H_2n-2OH
  D) C₂H_2n+1OH
  Show Answer
  The correct answer is D .
• Question 125: 50 cm³ of gas was collected over water at 10^oC and 765 mm Hg. Calculate the volume of the gas at s.t.p. if the saturated vapour pressure of water at 10 ^oC is 5mm Hg Options:
  A) 49.19 cm ³
  B) 48.87 cm ³
  C) 48.55 cm ³
  D) 48.23 cm ³
  Show Answer
  The correct answer is D .
• Question 126: The solubility curve shows the variation of solute concentration with Options:
  A) volume
  B) temperature
  C) vapour
  D) pressure
  E) weight
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  The correct answer is A .
• Question 127:

  Which of the following types of bonding does not involve the formation of new substances?

  Options:
  A) Metallic
  B) Covalent
  C) Co-ordinate
  D) Electrovalent
  Show Answer
  The correct answer is A .
• Question 128:

  Chromatography is used to separate components of mixture which differ in their rates of ?

  Options:
  A) diffusion
  B) migration
  C) reaction
  D) sedimentation
  Show Answer
  The correct answer is B .
• Question 129:

  Which process(es) is/are involved in the turning of starch iodide paper blue-black by chlorine gas?

  Options:
  A) chlorine attacks the starch to give the blue-black color
  B) chlorine attacks the iodide ion to give the blue-black color
  C) chlorine oxidizes the iodide ion to produce iodine which attacks the starch to give the blue-black color
  D) iodine attacks the starch to give the blue-black color
  Show Answer
  The correct answer is C .
• Question 130: The solution of a sample in a tube will be identified as a chloride if it gives Options:
  A) a white precipitate on addition of AgNO₃ and barium chloride solutions
  B) a white precipiate when acidified with HCI, and then AgNO₃ solution added
  C) a white precipitate when acidified with dilute HNO₃ and then AgNO₃ solution added
  D) a white precipitate when acidified with dilute H₂SO₄ and then barium nitrate solution added
  E) a pungent smell of chlorine gas when dilute HCI and MnO₂ are added
  Show Answer
  The correct answer is C .