Particles in matter are in a state of continuous motion
The particles present in matter are not stationary, but have a tendency to acquire motion. In fact they are in a state of continuous motion. The rate of movement of the particles is directly proportional to the thermal energy of the particles.
Particles in matter attract one another
The particles in matter attract one another. This attraction is inversely proportional to the distance between the particles. However, the magnitude of these inter-particle forces differs from one substance to another.
Particles in matter have spaces between them
Empty spaces called voids separate the particles from one another. The distance between them ranges from 10-8 cm to 10-5 cm. Due to these voids matter is able to disperse into one another bringing about diffusion.