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 1441:

  56.00cm³ of a gas at S.T.P. weighed 0.11g. What is the vapour density of the gas?
  [Molar volume of a gas at S.T.P = 22.4dm³]

  Options:
  A) 11.00
  B) 22.00
  C) 33.00
  D) 44.00
  Show Answer
  The correct answer is B .
• Question 1442:

  When heat is absorbed during a chemical reaction, the reaction is said to be

  Options:
  A) thermodynamic
  B) exothermic
  C) isothermal
  D) endothermic
  Show Answer
  The correct answer is D .
• Question 1443:

  C₃H₅ - COH₃ =CH₂

  The IUPAC nomenclature of the structure above is

  Options:
  A) 3-methybut-3-ene
  B) 2-methylbut-1-ene
  C) 2-ethylprop-1-ene
  D) 2-methylbut-2-ene
  Show Answer
  The correct answer is B .
• Question 1444: The metal that will react with water only in the form of steam to liberate hydrogen gas is? Options:
  A) calcium
  B) aluminium
  C) iron
  D) zinc
  Show Answer
  The correct answer is C .
• Question 1445: A stream of air was successively passed through three tubes X, Y and Z containing a concentrated aqueous solution of KOH, red hot copper powder and fused calcium chloride respectively. What was the composition of the gas emanating from tube Z? Options:
  A) CO₂ ad ithe inert gases
  B) N₂, CO₂ and the inert gases
  C) N₂ and the inert gases
  D) water vapour, N₂ and the inert gases
  Show Answer
  The correct answer is C .
• Question 1446:

  In the reaction

  C + 2HNO₃ → CO₂ + NO₂ + NO + H₂O nitric acid is acting as?

  Options:
  A) a reducing agent
  B) a nitrating agent
  C) an oxidizing agent
  D) a catalytic agent
  E) a neutralizing agent
  Show Answer
  The correct answer is C .
• Question 1447: Bleaching powder, CaOCI₂, H₂O, deteriorates on exposure to air because Options:
  A) it loses its water of crystallization
  B) atmospheric nitrogen displaces chlorine from it
  C) carbon (IV) oxide of the atmosphere displaceschlorine from it
  D) bleaching agents should be stored in solution
  Show Answer
  The correct answer is C .
• Question 1448: The vulcanizer's solution is prepared by dissolving rubber in Options:
  A) ethanol
  B) kerosine
  C) benzene
  D) petrol
  Show Answer
  The correct answer is C .
• Question 1449: Excess phosphorus was burnt in a gas jar and the residual gas passed successively over concentrated KOH solution and concentration H₂SO₄ before being collected in a flask. The gases collected are? Options:
  A) carbon (IV) oxide, nitrogen and the rare gases
  B) nitrogen and the rare gases
  C) carbon (IV) oxide, nitrogen (IV) oxide and the rare gases
  D) carbon (IV) oxide
  Show Answer
  The correct answer is C .
• Question 1450: The gas that gives brown colouration in brown ring test is Options:
  A) NO
  B) CO₂
  C) NO₂
  D) CO
  Show Answer
  The correct answer is A .