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 1401: 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 1402: MnO_4(aq) + 8H + _(aq) + 5Fe²⁺ → Mn^2+(aq) + 4H₂O_(I). The oxidation number of manganese in the above reaction changed from? Options:
  A) +7 to +2
  B) +6 to +2
  C) +5 to +2
  D) +4 to +2
  Show Answer
  The correct answer is A .
• Question 1403: which of these metals CANNOT replace hydrogen from alkaline solutions? Options:
  A) Aluminium
  B) Zinc
  C) Tin
  D) Iron
  Show Answer
  The correct answer is A .
• Question 1404:

  Which of the following produces relatively few ions in solution?

  Options:
  A) NaOH
  B) Ca(OH)${}_2$
  C) KOH
  D) AI(OH)${}_3$
  Show Answer
  The correct answer is D .
• Question 1405: What is the pH of 0.001 mol dm4 solution of sodium hydroxide? Options:
  A) 14
  B) 13
  C) 12
  D) 11
  E) 10
  Show Answer
  The correct answer is D .
• Question 1406: The constituents of baking powder that makes the dough to rise is Options:
  A) NaHCO₃
  B) NaOH
  C) Na₂CO₃
  D) NaCl
  Show Answer
  The correct answer is A .
• Question 1407: Copper sulphate solution is electolysed using platinum electrodes A. current of 0.193 amperes is passed for 2hrs. How many grams of copper are deposited? (cu = 63.5, F = 96500 coulombs) Options:
  A) 0.457g
  B) 0.500g
  C) 0.882g
  D) 0.914g
  E) 1.00g
  Show Answer
  The correct answer is A .
• Question 1408:

  One of the following is not a physical property of monosaccharides?

  Options:
  A) Monosaccharides get charred when heated
  B) Monosaccharides are water-soluble, sweet substances
  C) They are highly vital to the exploration of metals
  D) They can be reduced to sugar alcohols
  Show Answer
  The correct answer is C .
• Question 1409: The gaseous pollutant sulphur (IV)oxide is most likely to be detected in fairly reasonable quantities in the area around a plant for the Options:
  A) extraction of aluminium from bauxite
  B) production of margarine
  C) smelting of copper
  D) production of chlorine from brine
  Show Answer
  The correct answer is C .
• Question 1410:

  The molar ratio of carbon to hydrogen of a volatile liquid compound is 1: 2. 0. 12 g of the liquid on evaporation at s.t.p. gave 32 cm³ of vapour. The molecular formula of the liquid is

  [G.M.V =22.4 dm ³, C = 12, H = 1]

  Options:
  A) C ₃ H ₆
  B) C ₄H ₈
  C) C ₅C ₁₀
  D) C ₆H ₁₂
  Show Answer
  The correct answer is D .