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 1051: The enzyme used in the hydrolysis of starch to dextrin and maltose is Options:
  A) amylase
  B) diastatse
  C) invertase
  D) zymase
  Show Answer
  The correct answer is B .
• Question 1052: Which of the following statements is an exception in the assumptions of the kinetic theory of gases? Options:
  A) Gases are composed of many elastic particles
  B) The particles are of negligible size
  C) The particles are in constant random motion
  D) The particles are of negligible mass
  E) The particles collide with each other
  Show Answer
  The correct answer is D .
• Question 1053: In the reaction Fe + Cu²⁺ $\to$ Fe²⁺ + Cu,iron displaces copper ions to from copper. This is due to the fact that Options:
  A) irn is in the metallic from while the copper is in the ionic from
  B) the atomic weight of copper is greater than that of iron
  C) copper is greater than iron
  D) copper metal has more electrons than iron metal
  E) iron is higher in the electrochemical series than copper
  Show Answer
  The correct answer is E .
• Question 1054: Oxygen is a mixture of two isotopes O and O with relative abundances of 90% and 10% respectively. The relative atomic mass of oxygen is? Options:
  A) 16.0
  B) 16.2
  C) 17.0
  D) 18.0
  Show Answer
  The correct answer is B .
• Question 1055: Which of the following compounds can be represented by the molecular formula C2 H6O? Options:
  A) propanal
  B) ethanol
  C) methanoic acid
  D) glucose
  Show Answer
  The correct answer is B .
• Question 1056: A mixture of iodine and sulphur crystals can be separated by treatment with Options:
  A) Water to filter off sulphur
  B) carbon (IV) sulphide to filter off iodine
  C) ethanoic acid to filter off sulphur
  D) methanol to filter off iodine
  Show Answer
  The correct answer is B .
• Question 1057:

  ₁²D + ₁³T → ₂⁴He + ₀¹n + energy

  The reaction above illustrates

  Options:
  A) alpha decay
  B) artificial transmutation
  C) nuclear fussion
  D) nuclear fission
  Show Answer
  The correct answer is C .
• Question 1058:

  X + Y → Z. The rate equation for the chemical reaction above is ((-Δ[x])/Δt) = K[X]²[Y].

  The overall order of the reaction is

  Options:
  A) 0.0
  B) 1.0
  C) 2.0
  D) 3.09
  Show Answer
  The correct answer is D .
• Question 1059:

  H_2(g) + Br_2(g) → 2HBr_(g)

  The above reaction is carried out at 25^oC. ΔH is -72 kJ mol^-1 and ΔS is - 106 J mol^-1K^-1, the reaction will

  Options:
  A) not proceed spontaneously at the given
  B) proceed spontaneously at the given temperature
  C) proceed in the reverse direction at the given temperature
  D) proceed spontenously at lower temperature
  Show Answer
  The correct answer is A .
• Question 1060: Which of the activities is commonly used as a nuclear fuel Options:
  A) uranium
  B) palladium
  C) actium
  D) thorium
  Show Answer
  The correct answer is A .