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 1141: When dilute hydrochloric acid is added to iron(ll)sulphide, the gas evolved will? Options:
  A) turn moist red litmus paper blue
  B) turn lime water milky
  C) blacken lead acurate paper
  D) rekindle a glowing splint
  E) burn a sqeakly pop
  Show Answer
  The correct answer is C .
• Question 1142:

  Sieving is a technique used to separate mixtures containing solid particles of

  Options:
  A) small sizes
  B) large sizes
  C) different sizes
  D) the same size
  Show Answer
  The correct answer is C .
• Question 1143: Aluminium containers are frequently used to transport trioxonitrate (V) acid because aluminium Options:
  A) has a silvery-white appearance
  B) has a low density
  C) does not react with the acid
  D) does not corrode
  Show Answer
  The correct answer is C .
• Question 1144: The Avogadro number of 24g of magnesium is the same as that of Options:
  A) 1g of hydrogen molecules
  B) 16g of oxygen molecules
  C) 32g of oxygen molecules
  D) 35.5g of chlorine molecules
  Show Answer
  The correct answer is C .
• Question 1145:

  The enzyme that converts glucose to ethylalcohol is?

  Options:
  A) maltase
  B) zymase
  C) Diatase
  D) Invertase
  Show Answer
  The correct answer is B .
• Question 1146: The nucleus of an atom contains Options:
  A) protons only
  B) neurons only
  C) protons and electrons
  D) neutrons and electrons
  E) protons and neutrons
  Show Answer
  The correct answer is E .
• Question 1147: Which of the following substances is the most abundant in the universe? Options:
  A) Carbon
  B) Air
  C) Water
  D) Oxygen
  E) Hydrogen
  Show Answer
  The correct answer is E .
• Question 1148: Stainless steel is used for making Options:
  A) magnets
  B) tools
  C) coins and medals
  D) moving parts of clocks
  Show Answer
  The correct answer is B .
• Question 1149: CH₃CH₂Cl + KCN → CH₃CH₂CN + KClIn the reaction above, the cyanide is Options:
  A) hydrophobic
  B) hydrophilic
  C) nucleophilic
  D) electrophilic
  Show Answer
  The correct answer is C .
• Question 1150: The hybridization of the carbon atom in ethyne is Options:
  A) sp ⁴
  B) sp ³
  C) sp²
  D) sp
  E) s
  Show Answer
  The correct answer is D .