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 871:

  The combustion of carbon(ii)oxide in oxygen can be represented by equation.

  2CO + O${}_2$ → 2CO${}_2$

  Calculate the volume of the resulting mixture at the end of the reaction if 50cm${}_3$ of carbon(ii)oxide was exploded in 100cm${}_3$ of oxygen

  Options:
  A) 75cm${}^3$
  B) 125cm${}^3$
  C) 100cm${}^3$
  D) 50cm${}^3$
  Show Answer
  The correct answer is B .
• Question 872:

  Wrought iron is obtained by heating cast iron in a furnace with?

  Options:
  A) magnetite
  B) haematite
  C) carbon(ii)oxide
  D) calcium trioxosilicate(iv)
  Show Answer
  The correct answer is B .
• Question 873: 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 874: A sample of orange juice is found to have a pH of 3.80. What is he concentration of the hydroxide ion in the juice? Options:
  A) 1.6 x 10^-4
  B) 6.3 x 10^-11
  C) 6.3 x 10^-4
  D) 1.6 x 10^-11
  Show Answer
  The correct answer is B .
• Question 875: Which of the following groups of physical properties increases from left to right of the periodic table? i. Ionization energy ii. Atomic radius iii. Electronegativity iv. Electro affinity Options:
  A) i and ii
  B) i, ii and iii
  C) iii and iv
  D) i, ii, iii and iv
  Show Answer
  The correct answer is C .
• Question 876: A liquid that will dissolve fat is Options:
  A) Hydrochloric acid
  B) Calcium hydroxide
  C) Kerosene
  D) Water
  Show Answer
  The correct answer is B .
• Question 877: Clothes should be properly rinsed with water after bleaching because Options:
  A) the bleach decolourizes the clothes
  B) chlorine reacts with fabrics during bleaching
  C) the clothes are sterilized during bleaching
  D) hydrogen chloride solution is produced during bleaching
  Show Answer
  The correct answer is D .
• Question 878:

  Which trace gas in the atmosphere plays a significant role in the greenhouse effect?

  Options:
  A) Oxygen
  B) Argon
  C) Carbon dioxide
  D) Nitrogen
  Show Answer
  The correct answer is C .
• Question 879: The carbon atoms on ethane are Options:
  A) sp² hybridized
  B) sp³ hybridized
  C) sp⁴ hybridized
  D) sp hybridized
  Show Answer
  The correct answer is B .
• Question 880:

  Which important nitrogen-containing compound is produced in Haber's process?

  Options:
  A) NH${}_3$
  B) NO${}_2$
  C) NO
  D) HNO${}_3$
  Show Answer
  The correct answer is A .