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 1031: Which of the following types of reactions takes place between C₂H₄ and the halogens? Options:
  A) Substitution
  B) Polymerization
  C) Addition
  D) Saponification
  E) Oxidation
  Show Answer
  The correct answer is C .
• Question 1032:

  The IUPAC name of the compound CF${}_3$CHBrCl is

  Options:
  A) 2-chloro-2-bromo-1,1,1-trifluoroethane
  B) 2-bromo-2-chloro-1,1,1-trifluoroethane
  C) 1-bromo-1-chloro-2,2,2-trifluoroethane
  D) 1,1,1-trifluoro-2-bromo-2-chloroethane
  Show Answer
  The correct answer is B .
• Question 1033: The atomic radius of Li, Na and K are 1: 33A, 1. 54A and 1. 96A res pectively. Which of the following explaqins this gradation in atomic radius? Options:
  A) electropositivity decreases from Li to Na to K
  B) electronegativity decreases from Li to Na to K
  C) the number of the electron shells increases from Li to Na to K
  D) the elements are in the same period
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  The correct answer is C .
• Question 1034: Copper (II) tetraoxosulphate (VI) solution is electrolyzed using carbon electrodes. Which of the following are produced at the anode and cathode respectively ? Options:
  A) Copper and oxygen
  B) Oxygen and copper
  C) Hydrogen and copper
  D) Copper and hydrogen
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  The correct answer is B .
• Question 1035: In an equilibrium reaction, which of the following conditions indicates that maximum yield of the product will be obtained? Options:
  A) Equilibrium constant is very large
  B) ∆H - T∆S = O
  C) ∆ H > T ∆ S
  D) Equilibrium constant is less than zero
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  The correct answer is A .
• Question 1036: Which of the following hydrogen halides the highest entropy value? Options:
  A) HF
  B) HCl
  C) HBr
  D) HI
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  The correct answer is A .
• Question 1037: Chlorine is produced commercially by? Options:
  A) electrolysis of dilute hydrochloric acid
  B) electrolysis of brine
  C) neutralization of hydrogen chloride
  D) heating potassium trioxochlorate (V)
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  The correct answer is B .
• Question 1038: The idea of planetary electron was that of Options:
  A) Rutherford
  B) Thompson
  C) Bohr
  D) Dalton
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  The correct answer is A .
• Question 1039: The ability of carbon to form long chains is referred to as Options:
  A) Alkylation
  B) Acylation
  C) Carbonation
  D) Catenation
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  The correct answer is D .
• Question 1040: The ores that can be concentrated by flotation are Options:
  A) nitride ores
  B) sulphide ores
  C) oxide ores
  D) non-metals
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  The correct answer is B .