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 1811: The property of chlorine which causes hydrogen chloride to be more ionic than the chlorine molecules is its Options:
  A) electrovalency
  B) electron affinity
  C) electropositivity
  D) electronegativity
  Show Answer
  The correct answer is D .
• Question 1812:

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

  [ M = 27, Cl = 35.5]

  Options:
  A) MCl
  B) MCl${}_2$
  C) MCl${}_3$
  D) M${}_2$Cl${}_6$
  Show Answer
  The correct answer is C .
• Question 1813: The importance of sodium aluminate (III) in the treatment of water is to Options:
  A) cause coagulation
  B) neutralize acidity
  C) prevent goitre and tooth decay
  D) kill germs
  Show Answer
  The correct answer is A .
• Question 1814: 2.0g of a monobasic acid was made up to 250 cm³ with distilled water. 25.00 cm³ of this solution required 20.00cm³ of 0.1 M NaOH solution for complete neutralization. The molar mass of the acid is? Options:
  A) 200 g
  B) 160 g
  C) 100 g
  D) 50 g
  Show Answer
  The correct answer is C .
• Question 1815:

  Which one of the following is not a mixture?

  Options:
  A) Air
  B) Mercury
  C) Milk
  D) Cement
  Show Answer
  The correct answer is B .
• Question 1816:

  N_2(g) + 3H_2(g) ↔ 2NH_3(g) ΔH = -90 kJ

  In the equation above, the yield of ammonia can be decreased by

  Options:
  A) increasing the pressure
  B) removing the ammonia as it is formed
  C) increase the temperature
  D) adding a catalyst
  Show Answer
  The correct answer is C .
• Question 1817:

  On which of the following is the solubility of a gaseous substance dependent? 

  I. Nature of solvent 

  II. Nature of solute 

  III. Temperature 

  IV. Pressure

  Options:
  A) I, II, III and IV
  B) I and II only
  C) II only
  D) I, III and IV only
  Show Answer
  The correct answer is D .
• Question 1818:

  ₁²D + ₁³T → ₂⁴He + ₀¹n + energy

  The reaction above illustrates

  Options:
  A) alpha decay
  B) artificial transmutation
  C) nuclear fussion
  D) nuclear fission
  Show Answer
  The correct answer is C .
• Question 1819:

  An element having the atomic number 17 will resemble which of the following elements having atomic number as given below?

  Options:
  A) 33
  B) 35
  C) 18
  D) 19
  Show Answer
  The correct answer is B .
• Question 1820: The ion that will give a white precipitate with aqueous NaOH and soluble in excess of the base is Options:
  A) Ca²⁺
  B) Mg²⁺
  C) Zn²⁺
  D) Cu²⁺
  Show Answer
  The correct answer is C .