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 801:

  Which of the following is the best starting material for the preparation of oxygen? Heating of trioxonitrate (v) with

  Options:
  A) Pb
  B) Zn
  C) Ca
  D) Na
  Show Answer
  The correct answer is A .
• Question 802: In the extraction of iron, the waste gas from the furnace is a mixture of Options:
  A) PH₃ CO and CO₂
  B) CO and C
  C) N₂ CO and CO₂
  D) PH₃ and CO
  Show Answer
  The correct answer is A .
• Question 803:

  Which of the following pairs of substances will react further with oxygen to form a higher oxide?

  Options:
  A) CO${}_2$ and H${}_2$O
  B) NO and H${}_2$O
  C) CO and CO${}_2$
  D) SO${}_2$ and NO
  Show Answer
  The correct answer is D .
• Question 804:

  Soaps clean surfaces on the principlebased on?

  Options:
  A) viscosity
  B) floatation
  C) elasticity
  D) surface tension
  Show Answer
  The correct answer is D .
• Question 805: A gas exerts pressure on its container because Options:
  A) some of its molecules are moving faster than others
  B) of the collision of the molecules with each other
  C) of the mass of the molecules of gas
  D) the molecules of a gas colide with the walls of the container
  Show Answer
  The correct answer is D .
• Question 806:

  The pollutant usually presents in a city which generates its electricity from coal?

  Options:
  A) fog
  B) carbon(ii)oxide
  C) smog
  D) sulphur(iv)oxide
  Show Answer
  The correct answer is D .
• Question 807:

  

  The data in the table above shows the rate of reaction of nitrogen (ll) oxide with chlorine at 25^oC It can be concluded that doubling the initial concentration of NO increase the rate of reaction by a factor of

  Options:
  A) two
  B) three
  C) four
  D) five
  Show Answer
  The correct answer is C .
• Question 808: The product formed when propanol is heated over a copper catalyst in the absence of oxygen are Options:
  A) CH₃CH₂CHO and H₂
  B) CH₃CHO and CO₂
  C) CH₃CH₂COOH and H₂
  D) CH₃COOH and CO₂
  Show Answer
  The correct answer is D .
• Question 809: Chlorine gas is prepared in the laboratory by Options:
  A) adding concentrated hydrochloric acid to solid manganese (IV) oxide
  B) aciding concentrated tetraoxosulphate (VI) acid to solid sodium chloride
  C) dropping concentrated hydrochloric acid onto potassium tetraoxomanganate (VI) crystals
  D) aciding concentrated tetraoxosulphate (VI) acid to hydrochloric acid
  Show Answer
  The correct answer is A .
• Question 810:

  To what volume must 300cm${}^3$ of 0.60M sodium hydroxide solution be diluted to give a 0.40M solution?

  Options:
  A) 450cm${}^3$
  B) 300cm${}^3$
  C) 200cm${}^3$
  D) 150cm${}^3$
  Show Answer
  The correct answer is A .