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 1531:

  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 1532: In an endothermic reaction, if there is a loss in entropy the reaction will Options:
  A) be indeterminate
  B) be spontaneous
  C) not be spontaneous
  D) be at equilibrium
  Show Answer
  The correct answer is C .
• Question 1533:

  Which of the following does not support the fact that air is a mixture?

  Options:
  A) the constituents of air are in a fixed proportion by mass
  B) it cannot be represented with a chemical formula
  C) the constituents of air can be separated by physical by physical means
  D) none of the above
  Show Answer
  The correct answer is A .
• Question 1534:

  The process of rusting is an example of the formation of

  Options:
  A) Basic oxide
  B) Acidic oxide
  C) Reducing oxide
  D) Amphoteric oxide
  Show Answer
  The correct answer is A .
• Question 1535: When sodium nitrate dissolves in water, ∆H is positive. This means that? Options:
  A) the reaction is catalysed
  B) the reaction is complete
  C) the reaction is exothermic
  D) the reaction is endthermic
  E) sodium nitrate is highly soluble in water
  Show Answer
  The correct answer is D .
• Question 1536:

  In the reaction H_2(g)O $\to$ H_2(g) + 1/2O_2(g)

  ΔH = -2436000 KJ, which of the following has no effect on the equilibrium position?

  Options:
  A) Adding argon to the system
  B) Lowering the temperature
  C) Adding hydrogen to the system
  D) Decreasing the pressure
  E) Increasing the temperature
  Show Answer
  The correct answer is A .
• Question 1537: Chromatography is used to separate components of mixtures which differ in their rates of? Options:
  A) diffusion
  B) migration
  C) reaction
  D) sedimentaion
  Show Answer
  The correct answer is B .
• Question 1538: What volume of carbon (ll) oxide is produced by reacting excess carbon with 10 dm³ of oxygen? Options:
  A) 5 dm ³
  B) 20 dm ³
  C) 15 dm ³
  D) 10 dm ³
  Show Answer
  The correct answer is B .
• Question 1539:

  Which of the following describes the chemical property of acids?

  Options:
  A) None of the above
  B) Acid + XCO${}_3$ $\to$ Salt + H${}_2$O + NH${}_3$
  C) Acid + NaOH $\to$ Normal salt + CO${}_2$
  D) Acid + X${}_n$CO${}_3$ $\to$ Salt + H${}_2$O + CO${}_2$
  Show Answer
  The correct answer is D .
• Question 1540:

  What process would coal undergo to give coal gas, coal tar, ammoniacal liquor and coke?

  Options:
  A) Steam distillation
  B) Destructive distillation
  C) Liquefication
  D) Hydrolysis
  Show Answer
  The correct answer is B .