1) Gas: does not have a definite shape or volume and changes to liquid on cooling.
2) Liquid: has definite volume but not shape and changes to solid on cooling.
3) Solid: has definite shape and volume and changes to liquid on heating.
Cooling is change from liquids to solids.
There are five fundamental states of matter (gas, liquid, solid, plasma and Bose–Einstein condensate).
In solid, molecules are closely packed, stiff and do not changes of shape or volume. Solid object (for example wood) does not take on the shape of its container.
Liquids (for example water) have definite volume, but no fixed shape.
Gases (for example nitrogen and neeon) not have definite volume and fixed shape, it depends on its container.
