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 1511:

  MnO₂ + 2CI^- + 4H⁺ → MnO²⁺ + CI₂ + 2H₂O.

  The changes is oxidation numbers when the manganese, chloride and hydrogen ions react according to the above equation are respectively?

  Options:
  A) 2, 2, 4
  B) -1, -2, 4
  C) -2, 1, 0
  D) 2, 4, 0
  Show Answer
  The correct answer is C .
• Question 1512: The postulate of Dalton's atomic theory which still holds is that Options:
  A) atoms can neither be created nor destroyed
  B) the particles of the same element are exactly alike
  C) particles of different elements combine in simple whole number ratio
  D) all elemets are made of small indivisible particles
  Show Answer
  The correct answer is A .
• Question 1513: The type of isomerism shown by cis- and trans- isomers is Options:
  A) optical isomerism
  B) positional isomerism
  C) functional isomerism
  D) geometrical isomerism
  Show Answer
  The correct answer is D .
• Question 1514:

  The most abundant rare gas in the atmosphere is?

  Options:
  A) He
  B) Ne
  C) Ar
  D) Xe
  Show Answer
  The correct answer is C .
• Question 1515:

  Which of the following is a non-metal that remains liquid at room temperature?

  Options:
  A) Chlorine
  B) Phosphorus
  C) Bromine
  D) Helium
  Show Answer
  The correct answer is C .
• Question 1516: When chlorine Is passed into water and the resulting solution exposed to sunlight, the product formed are Options:
  A) Chlorine gas and hydrogen
  B) Oxygen and oxochlorate (I) acid
  C) Chlorine gas and oxochlorate (I) acid
  D) Hydrochloric acid and oxygen
  Show Answer
  The correct answer is D .
• Question 1517: When a solution of ammonium trioxocarbonate (IV) is added to a solution of an unknown salt, a white precipitate which is soluble in dilute hydrochloric acid but insoluble in ethanoic acid is formed. This indicates the presence of Options:
  A) Ca²⁺
  B) Na⁺
  C) Zn²⁺
  D) K⁺
  Show Answer
  The correct answer is A .
• Question 1518:

  Which type of salt is found in antacid medications and is used to relieve heartburn and indigestion?

  Options:
  A) Aluminum chloride
  B) Magnesium chloride
  C) Sodium chloride
  D) Calcium chloride
  Show Answer
  The correct answer is B .
• Question 1519:

  

  What is the IUPAC name for the hydrocarbon?

  Options:
  A) 2-ethyl-4-methylpent-2-ene
  B) 3,5-dimethylhex-3-ene
  C) 2,4-dimethylhex 3-ene
  D) 2-methyl-4-ethylpent-3-ene
  Show Answer
  The correct answer is A .
• Question 1520: The atomic numbers of two elements X and Y are 12 and 19 respectively. The bond of these two elements is? Options:
  A) ionic
  B) covalent
  C) neutral
  D) co-ordinate
  Show Answer
  The correct answer is B .