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 511:

  

  Which of the curves in the above graph illustrates the behaviour of an ideal gas?

  Options:
  A) W
  B) X
  C) Y
  D) Z
  Show Answer
  The correct answer is C .
• Question 512:

  The boiling of fat and aqueous caustic soda is referred to as

  Options:
  A) hydrolysis
  B) esterification
  C) acidification
  D) saponification
  Show Answer
  The correct answer is D .
• Question 513:

  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 514: An example of a secondary amine is? Options:
  A) propylene
  B) di-butylamine
  C) methylamine
  D) trimethylamine
  Show Answer
  The correct answer is B .
• Question 515: How many unpaired electron are in the p-orbitals of a fluorine atom? Options:
  A) 3
  B) $0$
  C) 1
  D) 2
  Show Answer
  The correct answer is C .
• Question 516:

  Na₂S₂O_3(aq) + 2HCl_(aq) → 2NaCl_(aq) + H₂O_(l)

  Which of the following would introduce the greatest increase in the rate of the chemical reaction above?

  Options:
  A) An increase in temperature and decrease in the concentration of the reactant
  B) A decrease in the volume and increase in the pressure of the reactant
  C) A decrease in the temperature and an incease in the concentration of the reactant
  D) An increase in temperature and an increase in the concentration of the reactant
  Show Answer
  The correct answer is D .
• Question 517:

  The volume occupied by 1.58g of a gas at S.T.P is 500cm${}^3$. What is the relative molecular mass of the gas?  [ G.M.V at S.T.P = 22.4dm${}^3$ ]

  Options:
  A) 28
  B) 32
  C) 44
  D) 71
  Show Answer
  The correct answer is D .
• Question 518:

  The scientist who stated that matter can be converted into energy is?

  Options:
  A) Boyle
  B) Lavoiser
  C) Avogadro
  D) Einstein
  Show Answer
  The correct answer is D .
• Question 519: In an endothermic reaction, if there is a loss in entropy the reaction will Options:
  A) be indeterminate
  B) be spontaneous
  C) not be spontaneous
  D) be at equilibrium
  Show Answer
  The correct answer is C .
• Question 520: The relative atomic mass of a naturally occurring lithium consisting of 90% Li and 10% Li is Options:
  A) 6.9
  B) 7.1
  C) 6.2
  D) 6.8
  Show Answer
  The correct answer is C .