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 1301: The property used in the industrial preparation of nitrogen and oxygen from air is Options:
  A) rate of diffusion
  B) density
  C) boiling point
  D) solubility
  Show Answer
  The correct answer is C .
• Question 1302: 50 cm³ of sulphur (IV) oxide, 800 cm³ of ammonia, 450 cm³ of hydrogen chloride, 1.0 cm³ of at 15°C. Which of the following is suitable for demonstrating the fountain experiment? Options:
  A) Sulphur (IV) oxide hydrogen chloride
  B) Carbon (IV) oxide and amonia
  C) Amonia and hydrogen chloride
  D) Carbon (IV) oxide and surphur (IV) oxide
  Show Answer
  The correct answer is C .
• Question 1303:

  How many pi ($\pi$) bonds are there in an alkene with six carbon atoms?

  Options:
  A) 4
  B) 6
  C) 5
  D) 3
  Show Answer
  The correct answer is D .
• Question 1304: Iron galvanized with zinc is cathodically protected from corrosion. This is because? Options:
  A) zinc has a more positive oxidation potential than iron
  B) zinc has less positive oxidation potential than iron
  C) bith have the same oxidation potential
  D) zinc is harder than iron
  Show Answer
  The correct answer is B .
• Question 1305:

  3H${}_{2(g)}$+ N2 ⇔ 2NH${}_{3(g)}$ ; H= -ve

  In the reaction above, lowering of temperature will

  Options:
  A) have no effect on the equilibrium position
  B) increase the rate of both the forward and reverse reactions equally
  C) favour the forward reaction
  D) favour the reverse reaction
  Show Answer
  The correct answer is C .
• Question 1306: 2.25g of a sample of an oxide of copper on reduction gave 2.0g of copper. 2.50g of another oxide of copper on reduction also gave 2.0g of copper. These results are in accordance with the law of? Options:
  A) constant composition
  B) conservation of matter
  C) multiple proportions
  D) definite proportions
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  The correct answer is C .
• Question 1307:

  A binary compound of oxygen with another element is referred to as?

  Options:
  A) Oxide
  B) Element
  C) Carbon
  D) Nitrogen
  Show Answer
  The correct answer is A .
• Question 1308: Deliquescent substances are also? Options:
  A) efflorescent
  B) anhydrous
  C) hygroscopic
  D) insoluble
  Show Answer
  The correct answer is C .
• Question 1309: Which of the following is NOT true of metals? Options:
  A) They are good conductors of electricity
  B) They ionize by electron loss
  C) Their oxides are acidic
  D) They have high melting points
  Show Answer
  The correct answer is C .
• Question 1310: Which of the following salts can be melted without decomposition? Options:
  A) Na₂CO₃
  B) CaCO₃
  C) MgCO₃
  D) ZnCO₃
  Show Answer
  The correct answer is A .