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 201:

  The IUPAC nomenclature of the compound

  H${}_3$C - CH(CH${}_3$) - CH(CH${}_3$) - CH${}_2$ - CH${}_3$

  Options:
  A) 3,4- dimethylhexane
  B) 2,3- dimethyl pentane
  C) 2- ethyl hexane
  D) 2,3- dimethylhexane
  Show Answer
  The correct answer is B .
• Question 202:

  Which of the following properties increases from left to right along the period but decreases down the group in the Periodic Table?

  I. Atomic Number   ii. Ionization energy  iii. Metallic character  iv. Electron affinity

  Options:
  A) ii and iii only
  B) ii and iv only
  C) iii and iv only
  D) i and ii only
  Show Answer
  The correct answer is B .
• Question 203: The major component of the slag from the production of iron is? Options:
  A) an alloy of calcium and iron
  B) coke
  C) impure iron
  D) calcium trioxosilicate (IV)
  Show Answer
  The correct answer is B .
• Question 204: Which of the following compounds will burn with a brick-red colour in a non-luminous Bunsen flame? Options:
  A) LiCI
  B) NaCl
  C) CaCl₂
  D) MgCl₂
  Show Answer
  The correct answer is C .
• Question 205:

  Which of the following is the best starting material for the preparation of oxygen? Heating of trioxonitrate (v) with

  Options:
  A) Pb
  B) Zn
  C) Ca
  D) Na
  Show Answer
  The correct answer is A .
• Question 206: When few drops of concentrated trioxonitrate(V) acid is added to an unknown sample and wanned an intense yellow colouration is observed. The likely functional group present in the sample is Options:
  A) NH₃—C—C=O
  B) CHO
  C) CO
  D) CNH₂
  Show Answer
  The correct answer is A .
• Question 207: Which of the following is not an alkali? Options:
  A) Ca(OH)₂
  B) NH₃
  C) NaOH
  D) Al(OH)₃
  Show Answer
  The correct answer is B .
• Question 208: 25cm³ of a 0.2 mol dm³ solution of Na₂CO₃ requires 20 cm³ of a solution of HCl for neutralization. The concentration of the HCl solution is Options:
  A) 0.5 mol dm³
  B) 0.6 mol dm³
  C) 0.2 mol dm³
  D) 0.4 mol dm³
  Show Answer
  The correct answer is A .
• Question 209: When a solution of silver (l) nitrate is saturated with hydrogen sulphide, a black precipitate forms which is? Options:
  A) H₂S
  B) Ag₂S
  C) PbS
  D) HNO₃
  E) S
  Show Answer
  The correct answer is B .
• Question 210: Geometric isomerism can exist in Options:
  A) hex-3-ene
  B) hexane
  C) prop-l-ene
  D) 3-methyl but -l-ene
  Show Answer
  The correct answer is A .