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 2151:

  

  In the diagram above. X is

  Options:
  A) SO₃
  B) SO₂
  C) S
  D) H₂S
  Show Answer
  The correct answer is B .
• Question 2152:

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

  [M = 27, Cl = 35.5]

  Options:
  A) MCl
  B) MCl₂
  C) MCl₃
  D) M₂Cl₆
  Show Answer
  The correct answer is C .
• Question 2153:

  

  Use the table above to answer this question. The element that is likely to participate in covalent rather than ionic bonding is

  Options:
  A) Z
  B) Y
  C) X
  D) W
  Show Answer
  The correct answer is C .
• Question 2154: The drying agent suitable for drying ammonia is Options:
  A) Calcium Chloride
  B) Calcium Oxide
  C) Phosphorus(V) Oxide
  D) Concentrated H₂SO₄
  Show Answer
  The correct answer is B .
• Question 2155: Hardness of water is caused by the presence of ions of Options:
  A) magnesium and silver
  B) cacium and magnesium
  C) sodium and potassium
  D) calcium and sodium
  Show Answer
  The correct answer is B .
• Question 2156: The shapes of CO${}_2$, H${}_2$O and CH${}_4$ respectively are Options:
  A) bent, linear and tetrahedral
  B) bent, tetrahedral and linear
  C) linear, bent and tetrahedral
  D) tetrahedral, linear and bent
  Show Answer
  The correct answer is C .
• Question 2157:

  Which of the following sets of operation will completely separate a mixture of sodium chloride, sand and iodine?

  Options:
  A) addition of water, filtration, evaporation to dryness and sublimation
  B) filtration, evaporation to dryness, addition of water and sublimation
  C) sublimation, filtration, evaporation and addition of water
  D) sublimation, addition of water, filtration and evaporation to dryness
  Show Answer
  The correct answer is A .
• Question 2158:

  CuO_(s) + H_2(g) ↔ Cu_(s) + H₂O_(l)

  What is the effect of increasing the pressure on the equilibrium reaction above?

  Options:
  A) The equilibrium is shifted to the left
  B) The equilibrium is shifted to the right
  C) There is no effect
  D) More H_2(g) is produced
  Show Answer
  The correct answer is C .
• Question 2159:

  SO${}_3$ is not directly dissolved in water in the industrial preparation of H${}_2$SO${}_4$ by the contact process because

  Options:
  A) SO${}_3$ is an acidic gas
  B) Acid is usually added to water and not water to acid
  C) The reaction between SO${}_3$ and water is violently exothermic
  D) SO${}_3$ does not dissolve readily in water
  Show Answer
  The correct answer is C .
• Question 2160: The solution with the lowest pH value is Options:
  A) 5 ml of (m/10) HCL
  B) 10 ml of (m/10) HCL
  C) 15 ml of (m/5) HCL
  D) 20 ml of (m/8) HCL
  Show Answer
  The correct answer is A .