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 1: The shape of ammonia molecule is? Options:
  A) trigonal planar
  B) octahedral
  C) square planar
  D) tetrahedral
  Show Answer
  The correct answer is A .
• Question 2: The solubility product of Cu(IO₃)₂ is 1.08 * 10^-7. Assuming that neither ions react appreciable with water to form H⁺ and OH^-, what is the solubility of this salt? Options:
  A) 2.7 * 10^-8 mol dm^-3
  B) 9.0 * 10^-8 mol dm^-3
  C) 3.0 * 10^-3 mol dm^-3
  D) 9.0 * 10^-3 mol dm^-3
  Show Answer
  The correct answer is D .
• Question 3: Air boiled out of water as steam is richer in Options:
  A) nitrogen and oxygen
  B) carbon (IV) oxide and oxygen
  C) noble gases and carbon (IV) oxide
  D) oxygen and noble gases
  Show Answer
  The correct answer is B .
• Question 4: An example of a hygroscopic substance is Options:
  A) CuO _(S).
  B) MgCL_2(S).
  C) CaCL_2(S).
  D) NaOH_(S).
  Show Answer
  The correct answer is A .
• Question 5: The major component of the slag from the production of iron is? Options:
  A) an alloy of calcium and iron
  B) coke
  C) impure iron
  D) calcium trioxosilicate (IV)
  Show Answer
  The correct answer is B .
• Question 6: Which of the following metals is the least reactive? Options:
  A) Pb
  B) Sn
  C) Hg
  D) Au
  Show Answer
  The correct answer is D .
• Question 7:

  

  Which of the curves above represents the behaviour of 1 mole of an ideal gas?

  Options:
  A) l
  B) ll
  C) lll
  D) lV
  Show Answer
  The correct answer is C .
• Question 8:

  Which of the following pairs of substances will react further with oxygen to form a higher oxide?

  Options:
  A) CO${}_2$ and H${}_2$O
  B) NO and H${}_2$O
  C) CO and CO${}_2$
  D) SO${}_2$ and NO
  Show Answer
  The correct answer is D .
• Question 9:

  Which of the following substances is a mixture?

  Options:
  A) Granulated sugar
  B) Seawater
  C) Sodium chloride
  D) Iron filling
  Show Answer
  The correct answer is B .
• Question 10: Which quantum number divides shells into orbitals? Options:
  A) principal
  B) Arzimuthal
  C) Magnetic
  D) Spin
  Show Answer
  The correct answer is B .