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 1411: The hydroxyl ion concentrated, (OH^-), in a solution of sodium hydroxide of pH 10.0 is? Options:
  A) 10^-10 mol dm^-3
  B) 10^-6 mol dm^-3
  C) 10^-4 mol dm^-3
  D) 10^-2 mol dm^-3
  Show Answer
  The correct answer is C .
• Question 1412: Which of the following ions will give a white precipitate with aqueous NaOH and soluble in excess of the base? Options:
  A) Ca²⁺
  B) Mg²⁺
  C) Zn²⁺
  D) Cu²⁺
  Show Answer
  The correct answer is C .
• Question 1413:

  With conc H₂SO₄ as catalyst

  CH₃COOH + C₂H₅OH → CH₃COOC₂H₅ + H₂O

  Options:
  A) esterification
  B) Condensation
  C) saponification
  D) neutralization
  Show Answer
  The correct answer is A .
• Question 1414: A chemical reaction which the hydration energy is greater than the lattice energy is referred to as Options:
  A) a spontaneous reaction
  B) an endothermic reaction
  C) an exothermic reaction
  D) a reversible reaction
  Show Answer
  The correct answer is C .
• Question 1415: In the electrolysis of brine the anode is Options:
  A) platinum
  B) copper
  C) zinc
  D) carbon
  Show Answer
  The correct answer is D .
• Question 1416:

  What is the common name for ethanoic acid?

  Options:
  A) Acetic acid
  B) Butyric acid
  C) Propionic acid
  D) Formic acid
  Show Answer
  The correct answer is A .
• Question 1417: A supersaturated solution is said to contain Options:
  A) more solute than it can dissolve at that temperature in the presence of undissolved solute
  B) as much solute as it can dissolve at that temperature in the presence of undissolved solute
  C) as much solute as it can dissolve at that temperature
  D) more solute than it can dissolve at that temperature
  Show Answer
  The correct answer is D .
• Question 1418: An element X forms the following compounds with chlorine; XCl₄, XCl₃, XCl₂. This illustrates the Options:
  A) law of multiple proportions
  B) law of chemical proportions
  C) law of simple proportions
  D) law of conservation of mass
  E) law of definite proportions
  Show Answer
  The correct answer is A .
• Question 1419: $PC{l}_{5(g)}\to PC{l}_{3(g)}+C{l}_{2(g)}$
  In the reaction above, an increase in pressure will Options:
  A) decelerate the reaction
  B) Increase the yield of $PC{l}_3$
  C) increase the yield of $PC{l}_5$
  D) accelerate the reaction
  Show Answer
  The correct answer is C .
• Question 1420:

  Using the metal activity series, the metal that can liberate hydrogen gas from steam is?

  Options:
  A) iron
  B) copper
  C) tin
  D) lead
  Show Answer
  The correct answer is A .