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 1671: In the electrolysis of brine, the anode is Options:
  A) platinum
  B) copper
  C) zinc
  D) carbon
  Show Answer
  The correct answer is D .
• Question 1672: Elements P, Q, R, S have 6, 11, 15, 17 electrons respectively, therefore, Options:
  A) P will form an electrovalent bond with R
  B) Q will form a covalent bond with S
  C) R will form an electrovalent bond with S
  D) Q will form an electrovalent bond with S
  E) Q will form a covalent bond with R
  Show Answer
  The correct answer is D .
• Question 1673:

  

  Consider the solubility curves of three salts X, Y and Z given in the diagram. If each solution of the salt contains 200 g, and is heated to 100^oC, which solution or solutions will deposit 100 g of the solute when suddenly cooled to 0^oC?

  Options:
  A) X only
  B) Y only
  C) Z only
  D) X and Z
  E) Y and Z
  Show Answer
  The correct answer is E .
• Question 1674: The constituent common to duralumin and alnico is Options:
  A) Co
  B) Mn
  C) Al
  D) Mg
  Show Answer
  The correct answer is C .
• Question 1675: Coal fire should not be used in poorly ventilated rooms because ? Options:
  A) of the accumulation of CO₂ which causes dep sleep
  B) it is usually too hot
  C) of the acumulation of CO which causes suffocation
  D) it removes most most of the gases in the rooms
  Show Answer
  The correct answer is C .
• Question 1676: If the difference in electronegativity of elements P and Q is 3.0. The bond that will be formed between them is Options:
  A) metallic
  B) covalent
  C) co-ordinate
  D) ionic
  Show Answer
  The correct answer is D .
• Question 1677:

  Chlorine gas is commonly used in the production of which of the following industrial compounds?

  Options:
  A) Chlorofluorocarbons (CFCs)
  B) Methane
  C) Ammonia
  D) Ethanol
  Show Answer
  The correct answer is A .
• Question 1678: The acid that is used to remove rust is Options:
  A) boric
  B) hydrochloric
  C) trioxonitrate (V)
  D) tetraoxosulphate (VI)
  Show Answer
  The correct answer is B .
• Question 1679: The carbon atoms in ethene are? Options:
  A) sp³ hybridized
  B) sp hybridized
  C) sp² hybridized
  D) not hybridized
  Show Answer
  The correct answer is C .
• Question 1680: Hydrogen is not liberated when trioxonitrate(v)acid reacts with zinc because Options:
  A) zinx is not rendered passive by acid
  B) hydrogen produced is oxidized to water
  C) oxides of nitrogen are produced
  D) all nitrates are soluble in water
  E) trioxonitrate(v)acid is a strong acid
  Show Answer
  The correct answer is E .