1. States of Matter
Chapter 3 Section 1

2. Solids What is Matter? States of Matter
The motion of the particles and the strength of attraction between the particles determine a material’s state of matter (by whether or not they hold their volume and shape).
4 states of matter: solid, liquid, gas, plasma
Solids
A solid is matter that has a definite volume and a definite shape.
Ex: pen – has cylindrical shape and volume does not change with location
Particles in Motion
The particles in a solid are packed tightly together and stay in fixed positions.
The particles vibrate within the solid.

3. Liquids Free To Move Viscosity
A liquid has a definite volume but no definite shape.
Ex: milk, water, oil
Liquids do not easily compress or expand.
Free To Move
The particles in a liquid have enough energy to move out of their fixed positions, but not enough to move far apart.
Viscosity
Some liquids flow more easily than others. The resistance of a liquid to flowing is viscosity.
High viscosity = flow slowly Ex: honey
Low viscosity = flow quickly Ex: water
Viscosity generally increases as liquids get colder.

4. Gases Surface Tension A gas can expand or be compressed. Vapor
Attractive forces cause the particles of a liquid to pull themselves together and resist being pushed apart.
The uneven forces acting on the particles on the surface of a liquid are called surface tension.
Gases
A gas has no definite volume or definite shape. Ex: air, helium, oxygen
Gas particles move at high speeds in all directions and spread apart, filling all the space available to them.
A gas can expand or be compressed.
Vapor
Matter that exists in the gas state, but is usually a liquid, is called vapor. Ex: water

5. Plasma A plasma is energized gas. Ex: lightning