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 1901: Which of the following statements is true about 2-methylpropane and butane Options:
  A) They are members of the same homologous series
  B) They have the same boiling point
  C) They have different number of carbon atoms
  D) They have the same chemical properties
  Show Answer
  The correct answer is A .
• Question 1902: Rare gases are suitable because they Options:
  A) are monoatomic
  B) form ions easily
  C) have duplet or octet electronic configuration in the outermost shells in their atoms
  D) are volatile gases
  Show Answer
  The correct answer is C .
• Question 1903: Which of the following compounds of trioxonitrate (V) will decomposes to give dinitrogen (i) oxide and water when heated? Options:
  A) NaNO₃
  B) Zn(NO₃)₂
  C) Cu(NO₃)₂
  D) NH₄NO₃
  Show Answer
  The correct answer is D .
• Question 1904: The atom of an element X is represented as _z^yX. The basic chemical properties of X depends on the value of Options:
  A) Y
  B) Z
  C) Y - Z
  D) Z - Y
  Show Answer
  The correct answer is B .
• Question 1905: Which of the following statements is FALSE about isotopes of the same element? Options:
  A) They have the same number of electrons in their outermost shells
  B) They have different atomic masses
  C) They have the same atomic number and the number of electrons
  D) They have the same atomic number but different umber of elelctrons
  Show Answer
  The correct answer is D .
• Question 1906: The property of concentrated H₂SO₄ that makes it suitable for preparing HNO₃ is its Options:
  A) boiling point
  B) density
  C) oxidizing properties
  D) dehydrating properties
  Show Answer
  The correct answer is C .
• Question 1907: Chromatography is used to separate components of mixtures which differ in their rates of? Options:
  A) diffusion
  B) migration
  C) reaction
  D) sedimentaion
  Show Answer
  The correct answer is B .
• Question 1908: The property which makes alcohol soluble in water is the Options:
  A) boiling point
  B) hydrogen bonding
  C) ionic character
  D) covalent nature
  Show Answer
  The correct answer is B .
• Question 1909: A compound gives an orange-red colour to non-luminous flame. This compound is likely to contain Options:
  A) Na⁺
  B) Ca²⁺
  C) Fe³⁺
  D) Fe²⁺
  Show Answer
  The correct answer is B .
• Question 1910: For a given solute, the concentration of its saturated solution in different solvents are Options:
  A) the same at the same temperature
  B) different at the same temperature
  C) the same at different temperature
  D) constant
  Show Answer
  The correct answer is B .