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 1701: The air around a petroleum refinery is most likely to contain? Options:
  A) CO₂, SO₃ and N₂O
  B) CO₂, CO and N₂O
  C) SO₂, CO and NO₂
  D) PH₃ H₂O and CO₂
  Show Answer
  The correct answer is C .
• Question 1702: If glucose is heated on the concentration tetraoxosulphate(iv)acid, it will be dehydrated Options:
  A) carbon
  B) carbon(iv)oxide
  C) ethane
  D) ethanol
  Show Answer
  The correct answer is A .
• Question 1703:

  How many bonding pair are present in carbon(iv)oxide?

  Options:
  A) 4
  B) 3
  C) 2
  D) 1
  Show Answer
  The correct answer is A .
• Question 1704: In which order are the following salts sensitive to light? Options:
  A) Agl > AgCl > AgBr
  B) AgCl > Agl > AgBr
  C) AgBr > AgCl > Agl
  D) AgCl > AgBr > Agl
  Show Answer
  The correct answer is D .
• Question 1705: The pressure on 100 cm³ of oxygen gas at 35°C is 750mm of Hg.What would be the volume of the gas if the pressure is increased to 1000mm of Hg without changing the temperature? Options:
  A) 133.3 cm³
  B) 85 cm³
  C) 75 cm³
  D) 65 cm³
  E) 58.3 cm³
  Show Answer
  The correct answer is C .
• Question 1706: Which of the following metals burns with brick red Options:
  A) Pb
  B) Ca
  C) Na
  D) Mg
  Show Answer
  The correct answer is B .
• Question 1707: The function of zinc electrode in a galvanic cells is that it Options:
  A) undergoes reduction
  B) serves as the positive electrode
  C) production electons
  D) uses up electrons
  Show Answer
  The correct answer is C .
• Question 1708: Na₂C₂O₄ + CaCl₂ → CaC₂O₄ + 2NaCl. Given a solution of 1.9g of sodium oxalate in 50g of water at room temperature, calculate the minimum volume of 0.1 M calcium oxalate using the above equation? Options:
  A) 1.40 χ 10² dm³
  B) 14.0 χ 10² cm³
  C) 1.40 χ 10^-2 dm^-2
  D) 14.0 χ 10^-2 cm³
  Show Answer
  The correct answer is A .
• Question 1709: Commercial bleaching can be carried out using Options:
  A) sulphur (IV) oxide and ammonia
  B) hydrogen sulphide and chlorine
  C) chlorine and sulphur (IV) oxide
  D) ammonia and chlorine
  Show Answer
  The correct answer is C .
• Question 1710:

  Sieving is a technique used to separate mixtures containing solid particles of

  Options:
  A) small sizes
  B) large sizes
  C) different sizes
  D) the same size
  Show Answer
  The correct answer is C .