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 211: Ethanol is soluble in water due to the presence of a Options:
  A) Carbonyl group
  B) Hydroxyl groupd
  C) Phenyl group
  D) Methyl group
  Show Answer
  The correct answer is B .
• Question 212:

  In the reaction:

  M + N → P

  ΔH = +Q kJWhich of the following would increase the concentration of the product?

  Options:
  A) Adding a suitable catalyst
  B) Increasing the concentration of P
  C) Increasing the temperature
  D) Decreasing the temperature
  Show Answer
  The correct answer is C .
• Question 213: For a general equation of the nature xP + yQ ≈ mR + nS, the expression for the equilibrium constant is? Options:
  A) k (p)^x (Q)^y
  B) (p)^x (Q)^y / (R)^m (S)ⁿ
  C) (R)^m (S)ⁿ / (p)^x (Q)^y
  D) m(R) n (S) / x(P) y (Q)
  Show Answer
  The correct answer is C .
• Question 214: The postulate of Dalton's atomic theory which still holds is that Options:
  A) atoms can neither be created nor destroyed
  B) the particles of the same element are exactly alike
  C) particles of different elements combine in simple whole number ratio
  D) all elemets are made of small indivisible particles
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  The correct answer is A .
• Question 215: The metal whose ore can be concentrated by passing it through a magnetic separator is Options:
  A) Zn
  B) Sn
  C) Cn
  D) Ca
  Show Answer
  The correct answer is B .
• Question 216:

  A gas occupies a volume of 1.5 liters at a pressure of 2 atmospheres. If the pressure is increased to 4 atmospheres while the temperature remains constant, what will be the new volume of the gas?

  Options:
  A) 6 liters
  B) 1.5 liters
  C) 0.75 liters
  D) 3 liters
  Show Answer
  The correct answer is C .
• Question 217:

  What are the possible oxidation numbers of an element if its atomic number is 17?

  Options:
  A) -1 and 7
  B) -1 and 6
  C) -3 and 5
  D) -2 and 6
  Show Answer
  The correct answer is A .
• Question 218:

  When ammonia and hydrogen ion bond together to form ammonium ion, the bond formed is called

  Options:
  A) electrovalent bond
  B) co-ordinate bond
  C) ionic bond
  D) covalent bond
  Show Answer
  The correct answer is B .
• Question 219: The gas that can be dried using concentrated tetraoxosulphate (VI) acid is Options:
  A) hydrogen bromide
  B) Sulphur (IV) oxide
  C) hydrogen sulphide
  D) ammonia
  Show Answer
  The correct answer is B .
• Question 220: Hydrogen sulphide gas can act as Options:
  A) an oxidizing agent
  B) a dehydrating agent
  C) a bleaching agent
  D) a precipitating agent
  Show Answer
  The correct answer is D .