Question

what are the characheristics of the particles?

Answer 1

Particles of matter are attracted to each other, so they tend to pull together. The particles can move apart only if they have enough kinetic energy to overcome this force of attraction. ... If particles do not have enough kinetic energy to overcome the force of attraction between them, matter exists as a solid.

Answer 2

particles of matter are very small 
particles of matter are constantly moving 
particles of matter have spaces between them 
particles of matter attract each other