Which of the following statements about a compound is incorrect? (i) A molecule of a compound has atoms of different elements. (ii) A compound cannot be separated into its constituent elements by physical methods of separation. (iii) A compound retains the physical properties of its constituent elements. (iv) The ratio of atoms of different elements in a compound is fixed.
Which of the following statements about a compound is incorrect? (i) A molecule of a compound has atoms of different elements. (ii) A compound cannot be separated into its constituent elements by physical methods of separation. (iii) A compound retains the physical properties of its constituent elements. (iv) The ratio of atoms of different elements in a compound is fixed.

Correct Answer: (iii) A compound retains the physical properties of its constituent elements

Explanation: Molecule of a compound is made up of atoms of various elements which cannot be separated from its elements by physical means of separation. The physical features of a compound are different from its components. Hence, the ratio of the different element is constant.