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 61:

  The reactions below represent neutralization reaction, in which of them is the value of H highest?

  Options:
  A) CH${}_3$CH${}_2$COOH + KOH → CH${}_3$CH${}_2$COOK + H${}_2$O
  B) NH${}_4$OH + HCL → NH${}_4$ + H${}_2$O
  C) NaOH + HCL → NaCL + H${}_2$O
  D) CH${}_3$COOH + NaOH → CH${}_3$COONa + H${}_2$O
  Show Answer
  The correct answer is C .
• Question 62:

  Which of the following is a physical change?

  Options:
  A) Exposing white phosphorus to air
  B) Burning kerosene
  C) Dissolving calcium in water
  D) Freezing ice cream
  Show Answer
  The correct answer is D .
• Question 63: Which of the following compounds will impart a brick-red colour to a non-luminious bunsen flame? Options:
  A) NaCl
  B) LiCl
  C) CaCl₂
  D) MgCl₂
  Show Answer
  The correct answer is C .
• Question 64:

  Which of the following compounds is an example of an electrovalent bond?

  Options:
  A) NaCl (sodium chloride)
  B) CO2 (carbon dioxide)
  C) H2O (water)
  D) CH4 (methane)
  Show Answer
  The correct answer is A .
• Question 65:

  The constituent common to duralumin and alnico is

  Options:
  A) Co
  B) Mn
  C) Al
  D) Mg
  Show Answer
  The correct answer is C .
• Question 66:

  MnO^-4_(aq) + Y + 5Fe²⁺_(aq) → Mn²⁺_(aq) + 5Fe²⁺_(aq) + 4H₂O_(l)
  In the equation above, Y is

  Options:
  A) 5H⁺_(aq)
  B) 4H⁺_(aq)
  C) 10H⁺_(aq)
  D) 8H⁺_(aq)
  Show Answer
  The correct answer is D .
• Question 67:

  Calculate the pH of 0.05 moldm${}^{-3}$ H${}_2$SO${}_4$

  Options:
  A) 1.30
  B) 1.12
  C) 1.00
  D) 0.30
  Show Answer
  The correct answer is A .
• Question 68: Oxygen-demanding waste are considered to be a water pollutant because they? Options:
  A) deplete oxygen which is necessary for the survival of aquatic organism
  B) increase oxygen which is necessary for survival of aquatic organism
  C) increase other gaseous substances which are necessary for the survival of aquatic organisms
  D) deplete other gaseous species which is necessary for the survival of aquatic organisms
  Show Answer
  The correct answer is A .
• Question 69:

  

  What is the IUPAC name for the compound?

  Options:
  A) 1-chloro-2-methylprop-2,3-ene
  B) 1-chloro-2-methylprop-2-ene
  C) 3-chloro-2-methylprop-1-ene
  D) 3-chloro-2methylprop-1,2-ene
  Show Answer
  The correct answer is C .
• Question 70:

  A solution contains 20g of solute in 180g of solvent. If the solvent is water, what is the concentration of the solution in terms of mass by mass percentage

  Options:
  A) 11.%
  B) 22.2%
  C) 10%
  D) 20%
  Show Answer
  The correct answer is C .