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 1781:

  

  Use the diagram to answer this question.

  The colour of the fountain water is

  Options:
  A) blue
  B) orange
  C) red
  D) yellow
  Show Answer
  The correct answer is C .
• Question 1782: The order in which a mixture of sand, ammonium chloride and sodium chloride can be separated is Options:
  A) dissolution → dryness → filtration → evaporation
  B) filtration → sublimation → evaporation → dryness
  C) sublimation → dissolution → filtration → evaporation
  D) dissolution → filtration → sublimation → evaporation
  Show Answer
  The correct answer is C .
• Question 1783: In the reaction E+F ↔ G+H, the backward reaction is favoured if the concentration of Options:
  A) F is increased
  B) E is increased
  C) E is reduced
  D) G is reduced
  Show Answer
  The correct answer is C .
• Question 1784:

  C₂H₅OH_(aq) → Y

  If the above reaction takes place in conc. H₂SO₄ at 180^o, Y represents

  Options:
  A) CH₄
  B) C₂H₅COOH
  C) C₂H₄
  D) CH₃OCH₃
  Show Answer
  The correct answer is C .
• Question 1785:

  X is a substance which liberates CO${}_2$ on treatment with concentrated H${}_2$SO${}_4$. A warm solution of X can decolorize acidified KMnO${}_4$. X is

  Options:
  A) HCOOH
  B) NaHCO${}_3$
  C) FeCO${}_3$
  D) H${}_2$C${}_2$O${}_4$
  Show Answer
  The correct answer is D .
• Question 1786: Natural water collected from rivers and ponds contain oxygen, carbon (IV) oxide and Options:
  A) nitrogen
  B) hydrogen
  C) chlorine
  D) sulphur
  E) oxide
  Show Answer
  The correct answer is A .
• Question 1787: Which of the following is a neutralization reaction? Options:
  A) Addition of sodium chloride solution to potassium chloride solution
  B) Addition of trioxonitrate (V) acid (nitric acid) to distilled water
  C) Addition of trioxonitrate (V) acid (nitric acid) to tetraoxosulphate (IV) acid (sulphuric acid)
  D) Addition of trioxonitrate (V) acid (nitric acid) to potassium trioxonitrate (V) (potassium nitrate) solution
  E) Addition of trioxonitrate (V) acid (nitric acid) to potassium hydroxide solution
  Show Answer
  The correct answer is E .
• Question 1788:

  

  The diagram above best illustrates the effect of decrease in

  Options:
  A) concentration
  B) temperature
  C) surface area
  D) pressure
  Show Answer
  The correct answer is A .
• Question 1789: The fundamental difference between the three states of matter is the Options:
  A) shape of their particles
  B) number of particles in each state
  C) shape of the container they occupy
  D) degree of movement of their particles
  Show Answer
  The correct answer is D .
• Question 1790: Geometric isomerism can exist in Options:
  A) hex-3-ene
  B) hexane
  C) prop-l-ene
  D) 3-methyl but -l-ene
  Show Answer
  The correct answer is A .