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 211: The constituents of baking powder that makes the dough to rise is Options:
  A) NaHCO₃
  B) NaOH
  C) Na₂CO₃
  D) NaCl
  Show Answer
  The correct answer is A .
• Question 212: One of the major uses of alkane is Options:
  A) as domestic and industrial fuel
  B) in the hydrogenation of oils
  C) in the textile industries
  D) in the production of plastics
  Show Answer
  The correct answer is A .
• Question 213:

  The most important element on the earth's crust is?

  Options:
  A) Nitrogen
  B) Hydrogen
  C) Oxygen
  D) Fluorine
  Show Answer
  The correct answer is C .
• Question 214: What volume of 1.5M solution of KOH would contain 0.045 moles Options:
  A) 67.50 cm³
  B) 30.00 cm³
  C) 6.75 cm³
  D) 3.00 cm³
  Show Answer
  The correct answer is B .
• Question 215:

  What is the chemical structure of soap and detergent molecules?

  Options:
  A) Hydrophilic head and hydrophobic tail
  B) Hydrophilic head and hydrophilic tail
  C) Hydrophobic head and hydrophobic tail
  D) Hydrophilic tail and hydrophobic head
  Show Answer
  The correct answer is A .
• Question 216:

  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 217:

  What is the product of the electrolysis of aqueous sodium chloride (NaCl) using inert electrodes?

  Options:
  A) Hydrogen gas at the cathode and chlorine gas at the anode
  B) Hydrogen gas at the cathode and oxygen gas at the anode
  C) Sodium metal at the cathode and chlorine gas at the anode
  D) Sodium metal at the cathode and oxygen gas at the anode
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  The correct answer is A .
• Question 218: In the reaction M + N P;∆H = + QKJ. Which of the following would increase the concentration of the product? Options:
  A) Decreaseing the concentration of N
  B) Increasing the concentration of P
  C) Adding a suitable catalyst
  D) Decreasing the temperature
  E) Increasing the temperature
  Show Answer
  The correct answer is E .
• Question 219:

  The heat of formation of ethene, C${}_2$H${}_4$ is 50 kJmol${}^{-1}$, and that of ethane, C${}_2$H${}_6$ is -82kJmol${}^{-1}$. Calculate the heat evolved in the process:

  C${}_2$H${}_4$ + H${}_2$ $\to$ C${}_2$H${}_6$

  Options:
  A) -122kJ
  B) -132kJ
  C) -88kJ
  D) -60kJ
  Show Answer
  The correct answer is B .
• Question 220:

  What is the concentration of a solution containing 2g of NaOH in 100cm³ of solution?

  [Na=23, O=16, H=1]

  Options:
  A) 0.05 moldm^-3
  B) 0.30 moldm^-3
  C) 0.50 moldm^-3
  D) 0.40 moldm^-3
  Show Answer
  The correct answer is C .