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 1251:

  A basic postulate of the kinetic theory of gases is that the molecules of a gas move in straight lines between collisions. This implies that

  Options:
  A) collisions are perfectly elastic
  B) forces of repulsion exist
  C) forces of repulsion and attraction are in equilibrium
  D) collisions are inelastic
  Show Answer
  The correct answer is B .
• Question 1252:

  

  The figure above shows the electrolysis of molten sodium chloride. Z is the

  Options:
  A) anode where the Cl${}^{-}$ ions are oxidized
  B) cathode where the Cl${}^{-}$ ions are reduced
  C) anode where the Na${}^{+}$ ions are reduced
  D) cathode where the Na${}^{+}$ ions are oxidized
  Show Answer
  The correct answer is A .
• Question 1253: Which of the following can have an isomer? Options:
  A) C₂H₄
  B) C₄H₁₀
  C) C₃H₈
  D) C₂H₆
  E) C₆H₆
  Show Answer
  The correct answer is B .
• Question 1254:

  CH_4(g) + Cl_2(g) → CH₃ Cl_(s) + HCl_(g)

  The major factor that influence the rate of the reaction above is

  Options:
  A) catalyst
  B) temperature
  C) concentration
  D) light
  Show Answer
  The correct answer is D .
• Question 1255: Phosphorus burns in oxygen according to the equation P₄ + 50₂ → P₄O₁₀. How many litres of oxygen will be required at S.T.P for complete oxidation of 12.4g of phosphorus? [P = 31,O = 16 and molar volume of a gas at S.T.P = 22.4 litres] Options:
  A) 5. 20
  B) 11. 20
  C) 2. 24
  D) 20. 20
  E) 6. 20
  Show Answer
  The correct answer is B .
• Question 1256: The alloy duralumin is used for the building of aeroplanes because it? Options:
  A) asborbs heat readily from sure thereby preventing the inside of the plane from getting cold at high attitudes
  B) reflects sunlight readily, thereby keeping the inside of the plane cool
  C) is extremely durable and possesses reflective ability
  D) is easily the lightest building material
  E) possesses both strenght and lightness
  Show Answer
  The correct answer is E .
• Question 1257:

  

  The major product of the dehydration of the compound above is

  Options:
  A) A
  B) B
  C) C
  D) D
  Show Answer
  The correct answer is A .
• Question 1258: There are basic particles from which matter called be made except Options:
  A) Salt
  B) Atom
  C) Ion
  D) Molecule
  Show Answer
  The correct answer is A .
• Question 1259: Detergents are manufacture with strength hydrocarbon chains is to make them Options:
  A) soluble
  B) biodegradable
  C) cheaper
  D) foamy
  Show Answer
  The correct answer is B .
• Question 1260:

  H${}_2$ S${}_{(g)}$ + Cl${}_{2(g)}$ → 2HCl${}_{(g)}$ + S${}_{(g)}$ In the reaction above, the substance that is reduced is

  Options:
  A) H${}_2$S
  B) S
  C) HCl
  D) Cl${}_2$
  Show Answer
  The correct answer is D .