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 1291: A substance S is isomorphous with another substance R. When a tiny crystals of S is added into a supersaturated solution of R? Options:
  A) S dissolves in the solution
  B) crystals of R are precipitated
  C) there is no observable change
  D) R and S react to generate heat
  Show Answer
  The correct answer is B .
• Question 1292: Reduction of alkanonoes with LialH₄ produces Options:
  A) primary alkanols
  B) secondary alkanols
  C) tertiary alkanols
  D) polyhydric alkanols
  Show Answer
  The correct answer is B .
• Question 1293: The ion that may be assumed to have negligible concentration in a sample of water that lathers readily with soap is? Options:
  A) Mg⁺
  B) K⁺
  C) CO₂^2-
  D) HCO₃
  Show Answer
  The correct answer is C .
• Question 1294:

  

  In the diagram above, X is the

  Options:
  A) Enthalphy
  B) Activated complex
  C) Activation energy
  D) Enthalphy change
  Show Answer
  The correct answer is D .
• Question 1295:

  A gaseous metallic chloride MCl consists of 20.22% of M by mass. The formula of the chloride is?

  [ M = 27, Cl = 35.5]

  Options:
  A) MCl
  B) MCl${}_2$
  C) MCl${}_3$
  D) M${}_2$Cl${}_6$
  Show Answer
  The correct answer is C .
• Question 1296:

  

  The tabulated results below were obtained by titration 10.0 cm³ of water with soup. The titration was repeated with the same sample of water after boiling. The ratio of permanent to temporary hardness is

  Options:
  A) 1.5
  B) 1.4
  C) 4.1
  D) 5.1
  Show Answer
  The correct answer is C .
• Question 1297: What amount of mercury would be liberated if the same quantity of electricity that liberates 0.65g of zinc is applied? Options:
  A) 2.01g
  B) 1.00g
  C) 4.02g
  D) 8.04g
  Show Answer
  The correct answer is C .
• Question 1298:

  Which of the following alkanes has a straight-chain structure?

  Options:
  A) Cyclopentane (C5H10)
  B) Isobutane (C4H10)
  C) 2 - methyl propane (C4H10)
  D) Pentane (C5H12)
  Show Answer
  The correct answer is D .
• Question 1299: Which of the following in aqueous solution is neutral to litmus? Options:
  A) NH₄CI
  B) NaCO₃
  C) FeCl₃
  D) NaCl
  Show Answer
  The correct answer is D .
• Question 1300: The greater the different in electronegativity between bonded atoms, the? Options:
  A) lower the polarity of the bond
  B) higher the polarity of the bond
  C) weaker the bond
  D) higher the possibility of the substance formed being a molecule
  Show Answer
  The correct answer is C .