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 751: A mixture of sugar and sulphur can be separated by Options:
  A) dissolution in water, evapouration and filtration
  B) filtration, evaporation and dissolution in water
  C) dissolution in water, filtration and evaporation
  D) evaporation, dissolution in water and filtration
  Show Answer
  The correct answer is C .
• Question 752: Which of the following is an example of a mixture? Options:
  A) Common salt
  B) Blood
  C) Sand
  D) Washing soda
  Show Answer
  The correct answer is B .
• Question 753:

  

  The compound above is the product of the oxidation of

  Options:
  A) 2-methlbutan-2-ol
  B) 2-methylbutan -1- ol
  C) 2, 3-dimethylprop 1-ol
  D) Pentan -2- ol
  Show Answer
  The correct answer is B .
• Question 754: A characteristic reaction of the compounds with the general formula C_nH_2n is Options:
  A) Esterification
  B) Polymerization
  C) Decarboxylation
  D) Substitution
  Show Answer
  The correct answer is B .
• Question 755: Which of the following is NOT used as a raw material in the Solvay process? Options:
  A) Ammonia
  B) Sodium chloride
  C) Calcium trioxocarbonate (IV)
  D) Sodium trioxocarbonate (IV)
  Show Answer
  The correct answer is D .
• Question 756:

  According to the Kinetic Theory an increase in temperature causes the kinetic energy of particles to

  Options:
  A) decrease
  B) increase
  C) be zero
  D) remain constant
  Show Answer
  The correct answer is B .
• Question 757:

  

  The diagram shown above represents the solubility curves of two salts, X and Y, in water, use this diagram to answer the question. If the molar mass of X is 36 g, the number of moles of X dissolved at 343 K is

  Options:
  A) 0.2 moles
  B) 0.7 moles
  C) 1.5 moles
  D) 2.0 moles
  E) 3.0 moles
  Show Answer
  The correct answer is B .
• Question 758: The following arrangement of elements in order of decreasing number of outer electrons; One of the elements is wrongly placed. Which is it? ALUMINIUM, CHLORINE, SILICON, MAGNESIUM AND SODIUM. Options:
  A) chlorine
  B) aluminium
  C) silicon
  D) magnesium
  E) sodium
  Show Answer
  The correct answer is B .
• Question 759:

  Mg²⁺_(aq) + 2e^->_(aq) → Mg_(s)E°_(volts) = 2.370

  Zn²⁺_(aq) + 2e^->_(aq) → Zn_(s)E°_(volts) = -0.763

  Cds²⁺_(aq) + 2e^->_(aq) → Cd_(s)E°_(volts) = 0.403

  Cu²⁺_(aq) + 2e^->_(aq) → Cu_(s)E°_(volts) = 0.340

  In the electrochemical series above, the strongest reducing agents is?

  Options:
  A) Cu _(s)
  B) Cd_(s)
  C) Znsub>(s)
  D) Mg_(s)
  Show Answer
  The correct answer is D .
• Question 760:

  If 1 litre of 2.2M sulphuric acid is poured into a bucket containing 10 litre of water,and resulting solution mixed thoroughly, the resulting sulpuric acid concentration will be?

  Options:
  A) 2.2 M
  B) 1.1 M
  C) O.22 M
  D) 0. 11 M
  E) 0.20 M
  Show Answer
  The correct answer is C .