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 101:

  Which of the following equimolar solutions, Na₂CO₃ Na₂ SO

  ₄CI FeCI₃ CH₃COONa,

  Have pH greater than 7?

  Options:
  A) FeCI ₃ and NH ₄CI
  B) Na₂CO₃, CH₃COONa and Na,Na₂SO₄
  C) Na₂CO₃ and CH₃COONa
  D) FeCI₃, CH₃COONa and NH₄CI
  Show Answer
  The correct answer is C .
• Question 102:

  

  The IUPAC nomenclature of the organic compound with the above structural formula is

  Options:
  A) 3-ethyl-2,5-dimethylhexane
  B) 4-ethyl-2,5-dimethylhexane
  C) 3-ethyl-2,5,5 - trimethylpentane
  D) 3-ethyl, 1,1,4-trimethylpentane
  Show Answer
  The correct answer is A .
• Question 103:

  A quantity of electricity liberates 3.6g of Silver from its salt. What mass of aluminium Will be liberated from its salt by the same quantity of electricity? [Al = 27, Ag = 108].

  Options:
  A) 2.7g
  B) 1.2g
  C) 0.9g
  D) 0.3g
  Show Answer
  The correct answer is A .
• Question 104:

  A few drop of conc HCL are added to about 10cm${}^3$ of a solution of PH 3.4. The PH of the resulting mixture is?

  Options:
  A) less than 3.4
  B) greater than 3.4
  C) unaltered
  D) the same as that of the pure water
  Show Answer
  The correct answer is A .
• Question 105:

  

  The I.U.P.A.C name for the compound is

  Options:
  A) isopropylethene
  B) acetylene
  C) 3- methylbutane
  D) 2-methylbutane
  E) 5-methylpentane
  Show Answer
  The correct answer is D .
• Question 106: Which of the following in aqueous solution is neutral to litmus? Options:
  A) NH₄CI
  B) NaCO₃
  C) FeCl₃
  D) NaCl
  Show Answer
  The correct answer is D .
• Question 107:

  

  In the above experiment, the litmus paper will initially

  Options:
  A) be bleached
  B) turn green
  C) turn red
  D) turn blue
  E) turn black
  Show Answer
  The correct answer is D .
• Question 108: Detergents have the general formula? Options:
  A) R(CH₂)_nOH
  B) RSO₃^-Na⁺
  C) RSO^-₂Na⁺
  D) RSO₂H
  Show Answer
  The correct answer is B .
• Question 109:

  The electronic configuration of an element is 1S${}^2$ 2S${}^2$ 2P${}^6$ 3S${}^2$ 3P${}^3$. How many unpaired electrons are there in the element?

  Options:
  A) 5
  B) 4
  C) 3
  D) 2
  Show Answer
  The correct answer is C .
• Question 110: How many valence electrons are contained in the element represented ³¹₁₅P? Options:
  A) 3
  B) 5
  C) 15
  D) 31
  Show Answer
  The correct answer is B .