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 1691:

  The heat of reaction can be determined experimentally using a device called a

  Options:
  A) Calorimeter
  B) Barometer
  C) Spectrometer
  D) Thermometer
  Show Answer
  The correct answer is A .
• Question 1692: Ethanol reacts with concentrated tetraoxosulphate (V) acid at a temperature above 170 ^oC to form Options:
  A) ethanone
  B) ethene
  C) ethyne
  D) ethanal
  Show Answer
  The correct answer is B .
• Question 1693:

  How many grams of methylacetylene (propyne) CH₃ - C Ξ CH will completely discharge the colour of 8g of bromine?

  (Br = 80, C = 12, H = 1)

  Options:
  A) 0.5
  B) 1.0
  C) 2.0
  D) 3.0
  E) 4.0
  Show Answer
  The correct answer is B .
• Question 1694: Hydrogen can be displaced from a lot alkaline solution by Options:
  A) Fe
  B) Cu
  C) Cn
  D) Sn
  Show Answer
  The correct answer is A .
• Question 1695: Which of the following compounds is used as a gaseous fuel? Options:
  A) CH₃ -CH₂ -CHO₂ -COOH
  B) CH₃ -C = CH
  C) CH₃ -CH₂ -CH₂ -CH₃
  D) CH₂ -CH₂ -CH₃
  Show Answer
  The correct answer is C .
• Question 1696:

  In the reaction

  C + 2HNO₃ → CO₂ + NO₂ + NO + H₂O nitric acid is acting as?

  Options:
  A) a reducing agent
  B) a nitrating agent
  C) an oxidizing agent
  D) a catalytic agent
  E) a neutralizing agent
  Show Answer
  The correct answer is C .
• Question 1697: When stem is passed over red hot carbon the substances produced are Options:
  A) hydrogen and trioxocarbonate (IV) acid
  B) hydrogen, oxygen and carbon (IV) oxide
  C) hydrogen and carbon (ii) oxide
  D) hydrogen and carbon (IV) oxide
  Show Answer
  The correct answer is C .
• Question 1698: The reaction Mg + H₂O → MgO + H₂ takes place only in the presence of? Options:
  A) excess Mg ribbon
  B) excess cold water
  C) very hot water
  D) steam
  Show Answer
  The correct answer is D .
• Question 1699: A hydrocarbon has an empirical formula CH and a vapour density of 39. Determine its molecular formula.[C = 12, H = 1] Options:
  A) C₂H₆
  B) C₃H₈
  C) C₃H₄
  D) C₆H₆
  Show Answer
  The correct answer is D .
• Question 1700: The oxidation state of oxygen in tetraoxosulphate(IV) acid is Options:
  A) -4
  B) +4
  C) -2
  D) +2
  Show Answer
  The correct answer is C .