Page 96 - Science Class 6 Times Publication

Differences between atoms and molecules

Atoms Molecules

1. Molecules are the smallest
1. An atom is the smallest particles of a substance
particle of an element which which can exit freely and
can take part in chemical contain all properties of the
reaction.
substance.

2. Atoms cannot be further 2. Molecules may be further
divided. divided into atoms.

States of matter

Matter exists in three states. They are solid, liquid and gas.

Solid

Solid substances have their xed shape and volume.

Generally, they are hard and rigid. Intermolecular
space is less but intermolecular force of attraction is
high. Due to this, molecules in solid are tightly packed.
Because of tightly packed molecules, solid cannot be

compressed.

Liquid Solid molecules

Liquid substances have xed volume but not  xed

shape. Liquid gains the shape of the container
in which it is kept. In liquid, molecules are loosely
packed. Intermolecular force is less than that in solid
but more than that in gas. Similarly, intermolecular
space in the liquid is more than that in solid but less
than that in the gas.

Therefore, liquid molecules can ow easily keeping
the distance between them constant. Thus, the liquid

has xed volume but not xed shape. Liquid molecules

Times' Crucial Science and Environment 92 Book 6