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 471:

  An element having the atomic number 17 will resemble which of the following elements having atomic number as given below?

  Options:
  A) 33
  B) 35
  C) 18
  D) 19
  Show Answer
  The correct answer is B .
• Question 472: The relative atomic mass of a naturally occurring lithium consisting of 90% Li and 10% Li is Options:
  A) 6.9
  B) 7.1
  C) 6.2
  D) 6.8
  Show Answer
  The correct answer is C .
• Question 473:

  220g of carbon dioxide contains ----- moles

  Options:
  A) 5
  B) 6
  C) 3
  D) 4
  Show Answer
  The correct answer is A .
• Question 474:

  Which of the following statements is correct about the periodic table?

  Options:
  A) Elements in the same period have the same number of valence electrons
  B) The valence electrons of the elements in the same period increase progressively across the period
  C) Elements in the same group have the same number of electron shells
  D) The non-metallic Properties of the elements tend to decrease across each period
  Show Answer
  The correct answer is B .
• Question 475: On heating anhydrous iron (ll) sulphate, in addition to producing iron (iii) oxide, which of the following is produced? Options:
  A) SO₂ (g) + FeS (s)
  B) SO₃ (g) +FeS(s)
  C) SO₂ (g) + SO₃(g)
  D) SO₂ (g) + H₂S (g)
  E) SO₃(g) + H₂S(g)
  Show Answer
  The correct answer is C .
• Question 476: Which of the following gives a precipitate when treated with NaOH solution? Options:
  A) AlCl₃
  B) NH₄CL
  C) CH₃COONa
  D) Na₂CO₃
  Show Answer
  The correct answer is A .
• Question 477: 3. 06 g of a sample of potassium trioxochlorate (V) (KCIO) was required to make a saturated solution with 10cm³ of water at 25^oC. The solubility of the salt at 25^oC is [K =39, Cl = 35.5, O = 16] Options:
  A) 5.0 moles dm³
  B) 3.0 moles dm³
  C) 2.5 moles dm³
  D) 1.0 molesv
  E) 0.5 moles dm³
  Show Answer
  The correct answer is C .
• Question 478: Water can be obtained as the only product during Options:
  A) combustion of hydrocarbons
  B) neutralization of an acid by base
  C) combustion of hydrogen
  D) electrolysis of brine
  E) boiling water
  Show Answer
  The correct answer is C .
• Question 479: At 25^oC and 1atm, a gas occupies a volume of 1.50dm³. What volume will it occupy at 100^oC and 1atm? Options:
  A) 1.88 dm³
  B) 6.00 dm³
  C) 18.80 dm³
  D) 18.80 dm³
  E) 60.00dm³
  Show Answer
  The correct answer is A .
• Question 480:

  The type of bonding in [Cu(NH${}_3$)${}^4$]${}^{2+}$ is 

  Options:
  A) coordinate
  B) electrovalent
  C) metallic
  D) covalent
  Show Answer
  The correct answer is A .