physics

Change liquid into solid state on cooling at a fixed temperature.

Change of solid in liquid at fixed temperature on heating.

The change of vapour directly into solid on cooling.

Change of solid directly into vapours on absorbing heat.

The force of attraction between the molecules of two different substance is called “FORCE OF COHESION” i.e. between glue and paper.

The inter-molecular force of attraction between the the molecules of the same substance called “FORCE OF COHESION.” i.e. water and water.

The molecules of a matter exert a force of attraction on each other . The force of attraction is called inter molecular force.

Matter is something which has mass, occupies space, and can be perceived by our senses .Hydrogen , milk ,pen etc.