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 151: An iron ore is known to contain 70.0% Fe₂O₃. The obtain from 80kg of the ore is?(Fe = 56, O = 16) Options:
  A) 35.0 kg
  B) 39.2 kg
  C) 70.0 kg
  D) 78.4 kg
  Show Answer
  The correct answer is B .
• Question 152:

  The scientist who stated that matter can be converted into energy is?

  Options:
  A) Boyle
  B) Lavoiser
  C) Avogadro
  D) Einstein
  Show Answer
  The correct answer is D .
• Question 153: A metallic oxide which reacts with both HCl and NaOH to give salt and water only can be classified as? Options:
  A) an acidic oxide
  B) a basic oxide
  C) a neutral oxide
  D) an amphoteric oxide
  Show Answer
  The correct answer is D .
• Question 154: Which of the following hydrocarbons is mainly used as fuel? Options:
  A) Methylene
  B) Ethylene
  C) Methane
  D) Ethyne
  Show Answer
  The correct answer is C .
• Question 155:

  The periodic classification is an arrangement of the elements

  Options:
  A) atomic weights
  B) isotopic weights
  C) molecular weights
  D) atomic numbers
  Show Answer
  The correct answer is D .
• Question 156: For a general equation of the nature xP + yQ → mR + nS, the expression for the equilibrium constant is Options:
  A) k [P]^x [Q]^y
  B) $\frac{[P{]}^x[Q{]}^y}{[R{]}^m[S{]}^n}$
  C) $\frac{[R{]}^m[S{]}^n}{[P{]}^x[Q{]}^y}$
  D) $\frac{m[R]n[S]}{x[P]y[Q]}$
  Show Answer
  The correct answer is C .
• Question 157: 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 158:

  

  The elections or two atoms Y and Z are arranged in shes as shown above. The bond formed between the atoms of Y and Z is

  Options:
  A) ionic
  B) convalent
  C) dative
  D) metallic
  Show Answer
  The correct answer is B .
• Question 159: Starch can be converted to ethyl alcohol by? Options:
  A) distillation
  B) fermentation
  C) isomerization
  D) cracking
  Show Answer
  The correct answer is B .
• Question 160:

  

  Copper sulphate solution was electrolysed using the apparatus show above. Which of the following changes are observed?

  Options:
  A) The bulb lights and copper is deposited at both electrodes
  B) the bulb lights and copper is deposited at the anode and disappears from the cathode
  C) the bulb lights and copper is deposited at the cathode and oxygen liberated at the anode
  D) the bulb lights and copper is deposited at the cathode and disappears from the anode
  E) the bulb lights but no additional changes are observed
  Show Answer
  The correct answer is D .