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 1251: The Arrhenius equation expresses the relationship between the speed of a reaction and its Options:
  A) Molecular collision
  B) Heat of reaction
  C) Catalyst
  D) Activation energy
  Show Answer
  The correct answer is A .
• Question 1252:

  Calculate the solubility in mol dm^-3 of 40g of CuSO₄ dissolved in 100g of water at 120^oC.

  [Cu = 64, S = 32, O = 16]

  Options:
  A) 4.00
  B) 2.50
  C) 0.40
  D) 0.25
  Show Answer
  The correct answer is B .
• Question 1253:

  Which of the following alkanes has a straight-chain structure?

  Options:
  A) Cyclopentane (C5H10)
  B) Isobutane (C4H10)
  C) 2 - methyl propane (C4H10)
  D) Pentane (C5H12)
  Show Answer
  The correct answer is D .
• Question 1254: Which of the following metals will displace iron from a solution of iron(ll)tetraoxosulphate(lV)? Options:
  A) Copper
  B) Mercury
  C) Silver
  D) Zinc
  E) Gold
  Show Answer
  The correct answer is D .
• Question 1255: The gas that is used for the treatment of cancer is Options:
  A) Neon
  B) Radon
  C) Xenon
  D) Argon
  Show Answer
  The correct answer is B .
• Question 1256: 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
  Show Answer
  The correct answer is A .
• Question 1257: Which of the following methods may be used to prepare trioxonitrate (V) acid (nitric acid) in the laboratory? Options:
  A) Heating ammonia gas with tetraoxosulphate (VI) acid
  B) Heating ammonium trioxonitrate (V) with tetraoxosulphate (VI) acid
  C) Heating sodium trioxonitrate (V) with tetraoxosulphate (VI) acid
  D) Heating potassium trioxonitrate (V) with calcium hydroxide
  E) Heating a mixture of ammonia gas and oxygen.
  Show Answer
  The correct answer is C .
• Question 1258:

  An element X has 127 neutrons and 82 electrons.

  Its atomic number is?

  Options:
  A) 209
  B) 105
  C) 45
  D) 82
  Show Answer
  The correct answer is D .
• Question 1259: Which of the following metals will liberate hydrogen from steam or dilute acid? Options:
  A) Copper
  B) Iron
  C) Lead
  D) Mercury
  Show Answer
  The correct answer is B .
• Question 1260: What volume of a 0.1 M H₃PO₄ will be required to neutralize 45.0 cm³ of a 0.2 M NaOH? Options:
  A) 10.0 cm³
  B) 20.0 cm³
  C) 27.0 cm³
  D) 30.0 cm³
  Show Answer
  The correct answer is D .