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 871:

  

  Use the above options to the question. The products formed on hydrolysis of

  Options:
  A) A
  B) B
  C) C
  D) D
  E) E
  Show Answer
  The correct answer is C .
• Question 872:

  What volume of oxygen is produced from the decomposition of 2 mole of KCIO₃ at s.t.p?

  [Molar volume of a gas at s.t.p = 22.4 dm³]

  Options:
  A) 22.4 dm³
  B) 33.6 dm³
  C) 44.8 dm³
  D) 67.2 dm³
  Show Answer
  The correct answer is D .
• Question 873:

  N₂O_4(aq) $\rightleftharpoons$ 2NO_2(g) $△$H = +ve

  In the reaction above, an increase in temperature will

  Options:
  A) Increase the reactant production
  B) Increase the value of the equilibrium constant
  C) Shift the equilibrium to the left
  D) Decrease the value of the equilibrium constant
  Show Answer
  The correct answer is B .
• Question 874: The most common ores of iron include Options:
  A) haematite, malachite and limonite
  B) chalcolite, calamine and bornite
  C) magnetite, haematite and bornite
  D) magnetite, chalcolite and bornite
  Show Answer
  The correct answer is C .
• Question 875: By means of filtration, one component can be obtained pure from an aqueous mixture of sodium chloride and Options:
  A) potassium nitrate
  B) sand
  C) lead nitrate
  D) sugar (glucose)
  E) starch
  Show Answer
  The correct answer is B .
• Question 876: The distance between the nuclei of chlorine atoms in a chlorine molecule is 0.194nm. The atomic radius of chlorine atom is Options:
  A) 0.097nm
  B) 0.914nm
  C) 0.388nm
  D) 2.388nm
  Show Answer
  The correct answer is A .
• Question 877: When excess ethanol is heated to 145^oC in the presence of concentrated H₂SO₄, the product is Options:
  A) ethyne
  B) diethyl sulphate
  C) diethyl ether
  D) acetone
  Show Answer
  The correct answer is C .
• Question 878:

  

  The diagram above represents an atom of

  Options:
  A) magnesium
  B) helium
  C) chlorine
  D) neon
  Show Answer
  The correct answer is A .
• Question 879:

  Stainless steel is an alloy made up of

  Options:
  A) Iron and zinc
  B) Copper and tin
  C) Iron and chromium
  D) Iron and carbon
  Show Answer
  The correct answer is C .
• Question 880: Which of the following is arranged in order of increasing electronegativity? Options:
  A) Chlorine, aluminium, magnesium, phosphorus, sodium
  B) sodium, magnesium, aluminium, phosphorus, chlorine
  C) Chlorine, phosphorus, phosphorous, aluminium, magnesium, sodium
  D) Sodium, chlorine, phosphorus, magnesium, aluminium
  Show Answer
  The correct answer is B .