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 581: The coloured nature of transition metal ions are associated with their partially filled Options:
  A) f- orbital
  B) s- orbital
  C) p-orbital
  D) d-orbital
  Show Answer
  The correct answer is D .
• Question 582: The general formula of an alkyl halide (which represent the halide) is? Options:
  A) C_nH_2n - ₂X
  B) C_nH_2n + ₁X
  C) C_nH_2n + ₂X
  D) C_nH_2nX
  E) C_nH_2n - 1
  Show Answer
  The correct answer is B .
• Question 583:

  The IUPAC name for CH${}_3$CH${}_2$COOCH${}_2$CH${}_3$ is

  Options:
  A) methylpropanoate
  B) ethylethanoate
  C) ethylpropanoate
  D) methylethanoate
  Show Answer
  The correct answer is C .
• Question 584:

  

  The solubility curve of a solid X (molecular mass = 160) is as show above 1,000 cm³ of a saturated solution of X at 80^oC. The weight of X crystalized out would be

  Options:
  A) 10 g
  B) 12 g
  C) 14 g
  D) 16 g
  E) 18 g
  Show Answer
  The correct answer is D .
• Question 585:

  At 25^o and zymase as catalyst,

  C₆H₁₂₆ → 2C₂H₅OH + 2CO₂ + energy

  The reaction above represented by the equation above is useful in the production of

  Options:
  A) propanol
  B) butanol
  C) methanol
  D) ethanol
  Show Answer
  The correct answer is D .
• Question 586:

  An organic compound with fishy smell is likely to have a general formula?

  Options:
  A) RCONHR${}^1$
  B) RCONH${}_2$
  C) RNH${}_2$
  D) RCOR${}^1$
  Show Answer
  The correct answer is C .
• Question 587:

  Which of the following methods can be used to remove temporary hardness from water?

  Options:
  A) Boiling
  B) Filtration
  C) sedimentation
  D) Chlorination
  Show Answer
  The correct answer is A .
• Question 588:

  Which halogen is a gas at room temperature and is pale yellow in color?

  Options:
  A) Chlorine (Cl)
  B) Fluorine (F)
  C) Iodine (I)
  D) Bromine (Br)
  Show Answer
  The correct answer is B .
• Question 589: The nucleus of the isotopes tritium contains Options:
  A) two neutrons with no protons
  B) one neutron and one proton
  C) two neutrons and one proton
  D) two neutrons, one proton and one electron
  Show Answer
  The correct answer is C .
• Question 590: The number of hydrogen ions in 4.9 g of tetraoxosulphate (IV) acid is?(S = 32, O =16, H = 1, Na = 6.02 x 10₂₃ Options:
  A) 3.01 x 10₂₂
  B) 6.02 x 10₂₂
  C) 3.01 x 10₂₃
  D) 6.01 x 10₂₃
  Show Answer
  The correct answer is B .