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 231:

  NH₄Cl_(s) ↔ NH_3(g) + HCL_(g)

  The reaction above can only attain equilibrium if

  Options:
  A) a gaseous reactant is added
  B) one of the products is removed
  C) it is in a closed system
  D) it is an open system
  Show Answer
  The correct answer is C .
• Question 232:

  Stainless steel is an alloy made up of

  Options:
  A) Iron and zinc
  B) Copper and tin
  C) Iron and chromium
  D) Iron and carbon
  Show Answer
  The correct answer is C .
• Question 233:

  Which of the following metals is the most essential in the regulation of blood volume, blood pressure and osmotic equilibrium?

  Options:
  A) Zinc
  B) Manganese
  C) Sodium
  D) Iron
  Show Answer
  The correct answer is C .
• Question 234:

  Which of the following metals is the most essential in the regulation of blood volume, blood pressure and osmotic equilibrium?

  Options:
  A) Zinc
  B) Manganese
  C) Sodium
  D) Iron
  Show Answer
  The correct answer is C .
• Question 235:

  The enzyme that converts glucose to ethylalcohol is?

  Options:
  A) maltase
  B) zymase
  C) Diatase
  D) Invertase
  Show Answer
  The correct answer is B .
• Question 236:

  I. It has a varied composition from one place to another.

  II. It constituents can be separated by physical means.

  III. It contains unreactive noble gases

  Which of the above shows that air is a mixture?

  Options:
  A) I and II only
  B) II and III only
  C) I and III only
  D) I, II and III
  Show Answer
  The correct answer is A .
• Question 237:

  A gaseous metallic chloride MCl_x consists of 20.22% of M by mass. The formula of the chloride is

  [M = 27, Cl = 35.5]

  Options:
  A) MCl
  B) MCl₂
  C) MCl₃
  D) M₂Cl₆
  Show Answer
  The correct answer is C .
• Question 238: An oxide XO₂ has a vapour density of 32. What is the atomic mass of X? Options:
  A) 20
  B) 32
  C) 14
  D) 12
  Show Answer
  The correct answer is B .
• Question 239:

  2-methylprop-1-ene is an isomer of

  Options:
  A) 3-methyl but-1-ene
  B) 2-methyl but-1-ene
  C) but-2-ene
  D) pent-2-ene
  Show Answer
  The correct answer is C .
• Question 240:

  

  The curve depicts titration between

  Options:
  A) Strong acid and strong base
  B) Strong acid and weak base
  C) Weak acid and weak base
  D) Weak acid and strong base
  Show Answer
  The correct answer is C .