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 481:

  Neutrons were discovered by?

  Options:
  A) James Chadwick
  B) Ernest Rutherford
  C) J.J Thompson
  D) John Dalton
  Show Answer
  The correct answer is A .
• Question 482: Which of the following molecules has two other positional isomers? Options:
  A) CH₃CH₂Br
  B) CH₃CHBrCH₃
  C) CBr₂F₂
  D) CH₂CHBrCH₂Br
  Show Answer
  The correct answer is D .
• Question 483:

  

  It can be deduced from the vapour pressure curves above that

  Options:
  A) liqiud 1 has the highest boiling point
  B) liquid ll has the highest boiling point
  C) liquid lll has the highest boiling point
  D) liquid lll has the lowest boiling point
  Show Answer
  The correct answer is C .
• Question 484:

  

  Use the following option above to answer this question. Which of the following compounds in solution will turn red litmus paper blue?

  Options:
  A) A
  B) B
  C) C
  D) D
  Show Answer
  The correct answer is C .
• Question 485: Which of the following is physical change? Options:
  A) Burning kerosene
  B) Freezing ice cream
  C) Exposing white phosphorus
  D) Dissolving calcium in water
  Show Answer
  The correct answer is B .
• Question 486:

  

  In the diagram above. X is

  Options:
  A) SO₃
  B) SO₂
  C) S
  D) H₂S
  Show Answer
  The correct answer is B .
• Question 487: The reaction 3C(s) + 2Fe₂O₃(s) = 4Fe(s) + 3CO₂(g): $\mathrm{\Delta }$H =46.0 kJ is Options:
  A) isothermic
  B) adiabatic
  C) isobaric
  D) endothermic
  E) exothermic
  Show Answer
  The correct answer is D .
• Question 488: 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 489: Smoke consist of? Options:
  A) solid particles dispersed in liquid
  B) solid or liquid particles dispersed in gas
  C) gas or liquid particles dispersed inliquid
  D) liquid particles dispersed inliquid
  Show Answer
  The correct answer is B .
• Question 490: 10.0 dm³ of water was added to 2.0 mol dm^-3 of 2.5dm³ solution of HCl. What is the concentration of the final solution in mol dm^-3? Options:
  A) 0.4
  B) 8.0
  C) 2.0
  D) 0.5
  Show Answer
  The correct answer is A .