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 1451:

  What volume of oxygen will remain after reacting 8cm of hydrogen gas with 20cm of oxygen gas

  Options:
  A) 10cm${}^3$
  B) 12cm${}^3$
  C) 14cm${}^3$
  D) 16cm${}^3$
  Show Answer
  The correct answer is D .
• Question 1452: Two organic compounds K and L were treated with a few drops of Fehling's solutions respectively . K formed a brick-red precipitate while L, remains unaffected. The compound K is an Options:
  A) alkanol
  B) alkane
  C) alkanal
  D) alkanone
  Show Answer
  The correct answer is C .
• Question 1453: A cycloalkane with the molecular formula C₅H₁₀ has ? Options:
  A) one isomer
  B) two isomers
  C) three isomers
  D) four isomers
  Show Answer
  The correct answer is C .
• Question 1454: When water drops are added to calcium carbide in a container and the gas is passed through a jet and lifted, the resultant flame is called an? Options:
  A) oxyethylene flame
  B) oxyhydrocarbon flame
  C) oxyacetylene flame
  D) oxymethane flame
  Show Answer
  The correct answer is C .
• Question 1455: The nucleus of the isotope tritium, contains? Options:
  A) two neutrons with no protons
  B) one neutron and one protons
  C) two neutrons and one proton
  D) two neutrons, one proton and one electron
  Show Answer
  The correct answer is C .
• Question 1456:

  

  In the diagram above. X is

  Options:
  A) SO₃
  B) SO₂
  C) S
  D) H₂S
  Show Answer
  The correct answer is B .
• Question 1457: When a crystal was added to the clear solution of its salt, the crystal did not dissolve and the solution remained unchange. This showed that the solution was Options:
  A) supersaturated
  B) concentrated
  C) unsaturated
  D) saturated
  Show Answer
  The correct answer is D .
• Question 1458:

  2SO_2(g) + O_2(g) $⟺$2SO_3(g)

  $△H=-395.7kJmo{l}^{-1}$

  In the reaction above, the concentration of 2SO_3(g) can be in creased by

  Options:
  A) decreasing the pressure
  B) decreasing the temperature
  C) the addition of catalyst
  D) increasing the temperature
  Show Answer
  The correct answer is B .
• Question 1459: The atom of an element X is represented as ${}_z^{y}X$. The basic chemical properties of X depend on the value of Options:
  A) Y
  B) Z
  C) Y - Z
  D) Z - Y
  Show Answer
  The correct answer is B .
• Question 1460:

  

  The IUPAC name for

  Options:
  A) 1-methlpentane
  B) 3-methylbutane
  C) 2-methylbutane
  D) 1-dimethylpropane
  E) 2-methylpentane
  Show Answer
  The correct answer is C .