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 261:

  What volume of (dm${}^3$) of water will be added to 10dm${}^3$ of 2.0 mol/dm${}^3$ HCL acid solution to give a final solution of 0.5 mol/dm${}^3$?

  Options:
  A) 30
  B) 40
  C) 20
  D) 50
  Show Answer
  The correct answer is B .
• Question 262: An element that can exist in two or more different structural forms which possess the same chemical properties is said to exhibit. Options:
  A) polymerism
  B) isotopy
  C) isomorphism
  D) isomerism
  E) allotrophy
  Show Answer
  The correct answer is E .
• Question 263: Which of the following metals will displace iron from a solution of iron(ll)tetraoxosulphate(lV)? Options:
  A) Copper
  B) Mercury
  C) Silver
  D) Zinc
  E) Gold
  Show Answer
  The correct answer is D .
• Question 264: The flame used by welders in cutting metals is Options:
  A) butane gas flame
  B) acetylene flame
  C) kerosene flame
  D) oxy-acetylene flame
  E) oxygen flame
  Show Answer
  The correct answer is D .
• Question 265:

  The sub-atomic particles located in the nucleus of an atomare?

  Options:
  A) neutron and proton
  B) proton and electron
  C) proton and ions
  D) neutron and electron
  Show Answer
  The correct answer is A .
• Question 266: The reaction between an organic acid and an alcohol in the presence of an acid catalyst is known as; Options:
  A) saponification
  B) dehydration
  C) esterification
  D) hydrolysis
  E) hydration
  Show Answer
  The correct answer is C .
• Question 267: To obtain pure carbon (II) oxide from its mixture with carbon (IV) oxide, the mixture should be Options:
  A) passed over heated copper (II) oxide
  B) bubbled through water
  C) bubbled through concentrated tetroxosulphate (VI) acid
  D) bubbled through sodium hydroxide
  Show Answer
  The correct answer is D .
• Question 268: Ethyne is passed through a hot tube containing organo-nickel catalyst to produce Options:
  A) isoprene
  B) polythene
  C) ethanol
  D) benzene
  Show Answer
  The correct answer is D .
• Question 269:

  A substance that is used as a ripening agent for fruits is

  Options:
  A) ethene
  B) propane
  C) methane
  D) butane
  Show Answer
  The correct answer is A .
• Question 270: The arrangement of particles in crystal lattices can be studied using Options:
  A) X - rays
  B) γ - rays
  C) α - rays
  D) β - rays
  Show Answer
  The correct answer is A .