All matter consists of many tiny and dispersed particles (atoms, molecules and ions)
These particles are constantly moving randomly
There are forces of attraction/repulsion between these particles
There are spaces between these particles
Evidence of the Particulate Theory of Matter:
Diffusion
Osmosis
Brownian Motion
Shape of Crystals
Dissolving of Crystals
Diffusion is the net movement of particles from an area of high concentration to an area of low concentration. This occurs because particles are in constant motion.
When the potassium manganate (VI) crystals are placed in the water, the particles slowly separate from each other and diffuse into the spaces between the water particles.
The ammonia gives off ammonia gas and the hydrochloric acid gives off hydrogen chloride gas. When these gas particles diffuse through the air meeting each other, they form a white ring called ammonium chloride. This proves that particles can move and have spaces.
Osmosis is the movement of water molecules from a region of high water concentration to a region of low water concentration through a partially permeable membrane.
Brownian Motion is the rapid, random movement of particles in a medium due to being bombarded with other particles. eg. dust in flashlight, pollen’s movement in water