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 381: The bond which joins two ethanoic acid molecules in the liquid state is Options:
  A) a covalent bond
  B) an ionic bond
  C) a dative covalent bond
  D) a hydrogen bond
  Show Answer
  The correct answer is D .
• Question 382:

  The only metal that is anti-bacterial is?

  Options:
  A) Iron
  B) Sodium
  C) Alluminium
  D) Copper
  Show Answer
  The correct answer is D .
• Question 383:

  If 100 cm³ of oxygen pass through a porous plug in 50 seconds, the time taken for the same volume of hydrogen to pass through the same porous plug is?

  (O = 16, H = 1)

  Options:
  A) 10.0 s
  B) 12.5 s
  C) 17.7 s
  D) 32.0 s
  Show Answer
  The correct answer is B .
• Question 384: Which of the following will change when a catalyst is added to a chemical reaction? Options:
  A) The activation energy
  B) The potential energy of the reactants
  C) The heat of the reaction
  D) the potential energy of the product
  Show Answer
  The correct answer is A .
• Question 385: 60cm³ of hydrogen are sparked with 20cm³ of oxygen at 100^oC and 1 atmosphere . The total volume of the residual gases in Options:
  A) 60 cm³
  B) 10 cm³
  C) 40 cm³
  D) 30 cm³
  E) 70 cm³
  Show Answer
  The correct answer is A .
• Question 386: Four elements W, X, Y and Z have atomic number 2,6,16 and 20 respectively. Which of these elements is a metal? Options:
  A) X
  B) W
  C) Z
  D) Y
  Show Answer
  The correct answer is C .
• Question 387: 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 388: The general formula for the alkanals is Options:
  A) ROH
  B) R₂CO
  C) RCOOR¹
  D) RCHO
  Show Answer
  The correct answer is D .
• Question 389: Which of the following substances is not a salt? Options:
  A) Aluminium oxide
  B) Sodium hydrogentrioxosulphate (V)
  C) Sodium trioxocarbonate (V)
  D) Zinc chloride
  Show Answer
  The correct answer is A .
• Question 390: 2.85g of an oxide of copper gave 2.52g of copper on reduction and 1.90g of another oxide gave 1.52g of copper on reduction. The data above illustrates the law of? Options:
  A) constant composition
  B) conservation of mass
  C) reciprocal proportions
  D) multiple proportions
  Show Answer
  The correct answer is D .