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 1331: The weakest attractive force that can be observed between two molecules is Options:
  A) ionic
  B) covalent
  C) coordinate covalent
  D) van der Waals
  Show Answer
  The correct answer is D .
• Question 1332: The salt formed from a weak acid and a strong base hydrolyzes in water to form Options:
  A) A saturated solution
  B) an acidic solution
  C) a buffer solution
  D) an alkaline solution
  Show Answer
  The correct answer is D .
• Question 1333: An organic compound containing 40.1% carbon and 6.6% hydrogen has an empirical formula of? Options:
  A) C₂H₄O₂
  B) C₂H₃O₂
  C) CH₂O
  D) CH₃O
  Show Answer
  The correct answer is C .
• Question 1334: The product formed when propanol is heated over a copper catalyst in the absence of oxygen are Options:
  A) CH₃CH₂CHO and H₂
  B) CH₃CHO and CO₂
  C) CH₃CH₂COOH and H₂
  D) CH₃COOH and CO₂
  Show Answer
  The correct answer is D .
• Question 1335: Fats and oils are? Options:
  A) addition products of long chain fatty acids and alkali
  B) addition products of long-chain fattyy acids and glycerol
  C) condensation products of long-chain fatty acids and glycerol
  D) condensation products of formaldehyde and glycerol
  E) liquids at 20°C
  Show Answer
  The correct answer is C .
• Question 1336: Hydrogen is used in oxy-hydrogen flames for melting metals because it Options:
  A) evolves a lot of heat when burnt
  B) combines explosively with oxygen
  C) is a very light gas
  D) is a rocket fuel
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  The correct answer is A .
• Question 1337: Which of the following processes takes place during electrolysis? Options:
  A) Positive ions are discharged at the anode bby gaining sufficient electrons to become neutral
  B) Negative ions are dicharged at the anode by gaining suficient electrons to become neutral
  C) Positive ions are discharged at the anode by losing sufficient electrons to become neutral
  D) Negative ions are discharge at the anode by losing sufficient electrons to become neutral
  E) Nothing happens
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  The correct answer is D .
• Question 1338:

  

  The diagram above represents an atom that can combine with chlorine to form

  Options:
  A) a covalent bond
  B) an electrovalent bond
  C) a hydrogen bond
  D) a co-ordinate bond
  Show Answer
  The correct answer is B .
• Question 1339:

  Cr₂O₇^2-_(aq) + 14H⁺_(aq) + 6l^-_(aq) → 2Cr³⁺_(aq) + 3l_(g) + 7H₂O_(I).

  The change in the oxidation number of oxygen in the equation above is?

  Options:
  A) 1
  B) 2
  C) 7
  D) 0
  Show Answer
  The correct answer is D .
• Question 1340: What is the correct IUPAC name for NO₂^-? Options:
  A) Dioxonitrate (IV) ion
  B) Trioxonitrate (III) ion
  C) Trioxonitrate (IV) ion
  D) Dioxonitrate (II) ion
  Show Answer
  The correct answer is D .