Understand that all matter is made of tiny particles, and explore atoms, molecules, and the kinetic theory.
All matter is made of extremely tiny particles, far too small to see individually, which are constantly in motion.
Why can you smell perfume from across a room, even without air currents?
Perfume particles spread out and move through the air due to their constant, random motion — a process called diffusion
Are particles of matter always at rest, or always moving?
Always moving, even in solids (though only vibrating in place, not travelling)
The kinetic theory explains that particle movement increases with temperature, and this explains why matter exists in different states.
Why does a gas expand to fill any container, while a solid keeps its shape?
Gas particles move freely with a lot of space between them, while solid particles are held tightly in fixed positions by strong forces
What happens to particle movement as temperature increases?
It increases, giving particles more kinetic energy
1. What is diffusion?
2. Are the particles that make up matter visible to the naked eye?
3. What happens to particle movement as temperature decreases?
4. Why does a gas diffuse faster than a liquid?
5. Give an example of diffusion in daily life.