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 581: The salt formed from a weak acid and a strong base hydrolyzes in water to form Options:
  A) A saturated solution
  B) an acidic solution
  C) a buffer solution
  D) an alkaline solution
  Show Answer
  The correct answer is D .
• Question 582:

  

  In the diagram above, X is the

  Options:
  A) Enthalphy
  B) Activated complex
  C) Activation energy
  D) Enthalphy change
  Show Answer
  The correct answer is D .
• Question 583:

  A sample of a substance containing only C and H burns in excess O₂ to yield 4.4g of CO₂

  And 2.7 g of H₂O. The empirical formula of a substance is?(C = 12, O = 16, H = 1)

  Options:
  A) CH₃
  B) CH₂
  C) CH₄
  D) C₂H₂₄
  Show Answer
  The correct answer is A .
• Question 584: A mixture of sugar and sulphur can be separated by Options:
  A) dissolution in water, evapouration and filtration
  B) filtration, evaporation and dissolution in water
  C) dissolution in water, filtration and evaporation
  D) evaporation, dissolution in water and filtration
  Show Answer
  The correct answer is C .
• Question 585: 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 .
• Question 586: If the temperature of a gas is increased? Options:
  A) the kinetic energy of the emolecules will decrease
  B) the pressure will decrease if the volume is constant
  C) the gas will occupy a greater volume if the pressure is constant
  D) the mass of the gas will decrease
  E) the pressure and volume will increase
  Show Answer
  The correct answer is C .
• Question 587:

  What process would coal undergo to give coal gas, coal tar, ammoniacal liquor and coke?

  Options:
  A) Steam distillation
  B) Destructive distillation
  C) Liquefication
  D) Hydrolysis
  Show Answer
  The correct answer is B .
• Question 588: Which of the following represents ethyl ethanonate? Options:
  A) CH₃CH₂CO₂CH₃
  B) (CH₃CO₂)₂O
  C) CH₃CH₂CO₂CH₂CH₃
  D) CH₃CO₂CH₂CH₃
  E) CH₃CH₂COCH₂CH₃
  Show Answer
  The correct answer is D .
• Question 589:

  Wrought iron is obtained by heating cast iron in a furnace with?

  Options:
  A) magnetite
  B) haematite
  C) carbon(ii)oxide
  D) calcium trioxosilicate(iv)
  Show Answer
  The correct answer is B .
• Question 590: When copper powder is heated with concentrated sulphuric acid, the gas produced is? Options:
  A) hydrogen sulphide
  B) sulphur dioxide
  C) sulphur trioxide
  D) hydrogen pentasulphide
  E) sulphur pentoxide
  Show Answer
  The correct answer is B .