Give appropriate terms for the following:

(a) The change of a solid into liquid.

(b) The force of attraction between the molecules of matter.

(c) The particles of matter which may or may not have independent existence.

(d) The process due to which a solid directly changes into its vapours.

(e) The change of vapour into a liquid.

Give two examples for the following:

(a) substances which can flow

(b) substances which can sublime

(c) substances which can diffuse.

Differentiate between an atom and a molecule.

What do you understand by:

(a) Intermolecular force of attraction,

(b) Intermolecular space?