Chapter 2, Section 1 Four States of Matter

Matter is made of atoms and molecules that are always in motion The state of matter is determined by how fast the particles move and how strongly they are attracted to each other.

States of Matter Physical forms in which a substance can exist. There are four: solid liquid gas plasma

Solids Definite shape and volume . The attraction between the particles are the strongest of the 4 states. Particles are very attracted to each other since extremely close together. Each atom vibrates in place.

Two Types of Solids Crystalline – orderly arrangement Amorphous – no orderly arrangement

Liquids Takes shape of its container (not definite) Have a definite volume. Some attraction between atoms Particles move fast enough for some to slide between one another

Properties of Liquids Surface tension – causes particles to “stick” together or to other surfaces Ex: drops of soda stuck in a straw Viscosity – a liquid’s resistance to flow Ex: pouring honey takes a long time

Water striders walk on water because of surface tension Maple syrup is more viscous than water

Gases No definite shape or volume Particle have the least amount of attraction between them Atoms move fast enough to break away completely from one another There is empty space between the particles Gas has Pressure – the measure of how much gas particles hit each other and the container they are in

The greater the amount of particles, the greater the pressure

Plasma Similar to gases: No definite shape or volume. Particles have very little attraction between them Particle Movement: atoms have been split apart to make positively and negatively charges particles.

Examples of Plasma Found on earth in fire, lightning, auroras, neon signs, and fluorescent lights Scientists think that most of the matter we know about in the Universe is plasma Ex: Stars

Gas Laws These laws describe the the behavior of gases in relationship to temperature and pressure Boyle’s Law Charles’ Law

Boyle’s Law For a fixed amount of gas at a constant temperature, the volume of a gas increases as the pressure decreases The volume of gas decreases as the pressure increases Pressure and volume have an inverse relationship

At constant pressure as temperature increases, volume increases As temperature decreases, volume decreases Charles’s Law