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 1: What amount of mercury would be liberated if the same quantity of electricity that liberates 0.65g of zinc is applied? Options:
  A) 2.01g
  B) 1.00g
  C) 4.02g
  D) 8.04g
  Show Answer
  The correct answer is C .
• Question 2: When air which contains the gases Oxygen, nitrogen, carbondioxide, water vapour and the rare gases, is passed through alkaline pyrogallol and then over quicklime, the only gases left are; Options:
  A) nitrogen and carbondioxide
  B) the rare gases
  C) nitrogen and oxygen
  D) nitrogen and the rare gases
  E) nitrogen, carbondioxide and the rare gases
  Show Answer
  The correct answer is D .
• Question 3: Carbohydrates are large molecules with the molecular formula C _x (H₂O)_y. In which of the following pairs is x not equal to y? Options:
  A) glucose and starch
  B) maltose and starch
  C) sucrose and fructose
  D) maltose and starch
  Show Answer
  The correct answer is A .
• Question 4: The substance that is used in the steel industry for the removal of carbon, sulphur and phosphorus impurities from pig iron is Options:
  A) oxygen
  B) chlorine
  C) nitrogen
  D) hydrogen
  Show Answer
  The correct answer is A .
• Question 5: Palm wine turns sour with time because? Options:
  A) the sugar content is converted into alcohol
  B) the carbon (IV) oxide formed during the fermentation process has a sour taste
  C) it is commonly adulterated by the tappers and sellers
  D) microbial activity results in the production of orgain acids within it
  Show Answer
  The correct answer is D .
• Question 6: A mixture is different from a compound because Options:
  A) the properties of a compound are those of its individual constituents while those of a mixture differ from its constituents
  B) a mixture is always homogeneous while a compound is not
  C) the constituent of a compound are chemically bound together while those of a mixture are not
  D) a mixture can be represented by a chemical formula while a compound cannot
  Show Answer
  The correct answer is C .
• Question 7: The solubility curve shows the variation of solute concentration with Options:
  A) volume
  B) temperature
  C) vapour
  D) pressure
  E) weight
  Show Answer
  The correct answer is A .
• Question 8: All these are electromagnetic waves except Options:
  A) White light
  B) Photon
  C) X-ray
  D) Infrared
  Show Answer
  The correct answer is B .
• Question 9: The filter in the cigarette reduce the nicotine construct by Options:
  A) burning
  B) absorption
  C) evaporation
  D) absorption
  Show Answer
  The correct answer is A .
• Question 10: What properties of duralumin make it more useful than its constituent metals? Options:
  A) It is heavy with a high melting point
  B) It is malleable and has high density
  C) It is strong and light
  D) It is hard and ductile
  Show Answer
  The correct answer is C .