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 1001: In countries where the temperature fall below 273k, salt always spilled on the ray road in order to Options:
  A) increase the making point office
  B) increase the density of the ice
  C) make the ice impure
  D) rinse the making point of the ice
  Show Answer
  The correct answer is A .
• Question 1002:

  Which of the following is a characteristic property of acids?

  Options:
  A) Turn litmus paper blue
  B) Bitter taste
  C) pH value above 7
  D) React with metals to produce hydrogen gas
  Show Answer
  The correct answer is D .
• Question 1003:

  When heat is absorbed during a chemical reaction, the reaction is said to be

  Options:
  A) thermodynamic
  B) exothermic
  C) isothermal
  D) endothermic
  Show Answer
  The correct answer is D .
• Question 1004: The condition required for corrosion to take place is the presence of Options:
  A) water and carbon (IV) oxide
  B) water, carbon (IV) oxide and oxygen
  C) oxygen and carbon (IV) oxide
  D) water and oxygen
  Show Answer
  The correct answer is D .
• Question 1005: Coal gas is made up of carbon (II) oxide, hydrogen and? Options:
  A) nitrogen
  B) air
  C) argon
  D) methane
  Show Answer
  The correct answer is D .
• Question 1006: Starch can be converted to ethyl alcohol by Options:
  A) distillation
  B) fermentation
  C) isomerization
  D) cracking
  E) cooking
  Show Answer
  The correct answer is B .
• Question 1007: The oxidation number of manganese in KMnO₄ is? Options:
  A) +1
  B) +3
  C) +5
  D) +7
  E) +2
  Show Answer
  The correct answer is D .
• Question 1008:

  

  In the diagram above, X is the

  Options:
  A) Enthalphy
  B) Activated complex
  C) Activation energy
  D) Enthalphy change
  Show Answer
  The correct answer is D .
• Question 1009: The method that can be used to convert hard water to soft water is Options:
  A) chlorination
  B) passage over activated charcoal
  C) the use of an ion-exchange resin
  D) aeration
  Show Answer
  The correct answer is C .
• Question 1010: When sodium trioxocarbonate (IV) decahydrate loses its water of crystallization to the atmosphere, the process is Options:
  A) deliquescence
  B) efflorescence
  C) hygroscopic
  D) effervesecence
  Show Answer
  The correct answer is B .