Step-by-step explanation:
Substances in which molecules are closely packed together due to strong force of attraction are called solid substances.
This means a solid has a definite volume and has a definite shape.
Substances in which molecules are slightly less closely packed together are called liquid substances.
This means a liquid has a definite volume and does not have a definite shape. They occupy the shape of vessel in which they are placed.
Substances in which molecules are not packed together as they have weak vander forces between them are called gaseous substances.
This means a gas does not have a definite volume and does not have a definite shape. Volume of gases changes to match the volume of vessel in which they are kept.