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 1191: The electronic configuration of Mg ²⁺ is Options:
  A) ls ²2s ²2P ⁶3s²3P²
  B) Is²2s²2P⁶
  C) ls²2s²2p⁶3s²
  D) ls²2s²2P⁴
  Show Answer
  The correct answer is B .
• Question 1192: Which of the following gases contains the highest number of atoms at s.t.p? Options:
  A) 6 moles of neon
  B) 3 moles of oxygen
  C) 2 moles of chlorine
  D) 1 mole of ethane
  Show Answer
  The correct answer is A .
• Question 1193: In general, an increase in temperature increases the solubility of a solute in water because? Options:
  A) more solute molecules collide with each other
  B) most solutes dissolve with the evoltion of heat
  C) more solute molecules dissociate at hihger temperatures
  D) most solutes dissolve with absorption of heat
  Show Answer
  The correct answer is C .
• Question 1194: A mixture of petrol and water can be separated through Options:
  A) centrifugation
  B) distillation
  C) the use of separating funnel
  D) the use of filter paper
  Show Answer
  The correct answer is C .
• Question 1195: Which of the following pairs of substance will react further with oxygen to form a higher oxide? Options:
  A) CO₂ and H₂O
  B) NO and H₂O
  C) CO and CO₂
  D) SO₂ and NO
  Show Answer
  The correct answer is D .
• Question 1196: The catalyst used in the contact process for the manufacture of tetraoxosulphate (VI) acid is Options:
  A) manganes (IV) oxide
  B) manganese (ll) tetraoxosulphate (VI)
  C) vanadium (V) oxide
  D) iron metal
  Show Answer
  The correct answer is C .
• Question 1197:

  

  The diagram above represents the formation of

  Options:
  A) a metallic bond
  B) an electrovalent bond
  C) a covalent bond
  D) a coordinate covalent bond
  Show Answer
  The correct answer is C .
• Question 1198:

  Which of the following pairs of substances will react further with oxygen to form a higher oxide?

  Options:
  A) CO${}_2$ and H${}_2$O
  B) NO and H${}_2$O
  C) CO and CO${}_2$
  D) SO${}_2$ and NO
  Show Answer
  The correct answer is D .
• Question 1199: The shape of ammonia molecules is Options:
  A) trigonal planar
  B) octahedral
  C) square planar
  D) tetrahedral
  Show Answer
  The correct answer is A .
• Question 1200:

  When heat is absorbed during a chemical reaction, the reaction is said to be

  Options:
  A) thermodynamic
  B) exothermic
  C) isothermal
  D) endothermic
  Show Answer
  The correct answer is D .