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 1: The number of isomers that can be obtained from 04R0 is Options:
  A) 3
  B) 4
  C) 1
  D) 5
  E) 2
  Show Answer
  The correct answer is E .
• Question 2: Solutions X, Y, and Z have PH values 3.0. 5. 0 and 9. 0 respectively. Which of the following statements is correct? Options:
  A) All the solutions are acidic
  B) All the solutions are basic
  C) Y and Z are more acidic than water
  D) Y is more acidic than X
  E) Z is the least acidic
  Show Answer
  The correct answer is E .
• Question 3:

  The reactivity of fluorine is due to?

  Options:
  A) its high electro negativity
  B) small size of fluorine atom
  C) availability of D-orbitals
  D) strong f-f bond
  Show Answer
  The correct answer is A .
• Question 4: The product of the electrolysis of dilute sodium hydroxide using platinum electrodes are Options:
  A) Hydrogen and oxygen gases
  B) Water and hydrogen gas
  C) Water and sodium metal
  D) Sodium metal and oxygen gas
  Show Answer
  The correct answer is A .
• Question 5:

  CH₃COOH_(g) → H_4(g) + CO_2(g)

  The reaction above is

  Options:
  A) Carboxylation
  B) Decarboxylation
  C) Acidification
  D) Esterification
  Show Answer
  The correct answer is B .
• Question 6: Addition of aqueous ammonia to a solution of Zn⁺⁺ gives a white precipitate which dissolves in an excess of ammonia because? Options:
  A) zinc is amphoteric
  B) zinc hydroxide is readily soluble
  C) zinc forms a complex which is readily soluble in excess ammonia
  D) ammonia solution is a strong base
  Show Answer
  The correct answer is C .
• Question 7:

  A balanced chemical equation obeys the law of

  Options:
  A) conservation of mass
  B) definite proportions
  C) multiple proportions
  D) conservation of energy
  Show Answer
  The correct answer is A .
• Question 8: 3. 06 g of a sample of potassium trioxochlorate (V) (KCIO) was required to make a saturated solution with 10cm³ of water at 25^oC. The solubility of the salt at 25^oC is [K =39, Cl = 35.5, O = 16] Options:
  A) 5.0 moles dm³
  B) 3.0 moles dm³
  C) 2.5 moles dm³
  D) 1.0 molesv
  E) 0.5 moles dm³
  Show Answer
  The correct answer is C .
• Question 9:

  When water drops are added to calcium carbide in a container and the gas produced is passed through a jet and lighted, the resultant flame is called an?

  Options:
  A) Oxyethene
  B) Oxyhydrocarbon flame
  C) Oxyacetylene flame
  D) Oxymethane flame
  Show Answer
  The correct answer is C .
• Question 10:

  A chemical widely used as a fertilizer is?

  Options:
  A) galena
  B) bauxite
  C) emerald
  D) nitrochalk
  Show Answer
  The correct answer is D .