Chapter 1- States of matter

Describe the arrangement and movement of particles in solids

Closely packed together in a regular arrangement. Vibrate in fixed positions.

Describe the arrangement and movement of particles in liquids

Closely packed together but able to move past each other. Random arrangement. Vibrate and move around each other.

Describe the arrangement and movement of particles in gases

Well separated in a random arrangement. Vibrate and move freely at high speeds.

Compare the relative energies of particles in solids, liquids and gases

Particles in a solid have the least energy and particles in a gas have the most energy.

State change from solid to liquid

Melting

State change from liquid to solid

Freezing

State change from liquid to gas

Evaporation

State change from gas to liquid

Condensation

Solid changing directly into a gas

Sublimation

Describe the forces between particles in solids, liquids and gases

Solids have strong forces of attraction. Liquids have weaker attractive forces. Gases have almost no intermolecular forces.

Effect of temperature on the volume of a gas

As temperature increases, volume increases.

Effect of pressure on the volume of a gas

As pressure increases, volume decreases. As pressure decreases, volume increases.

Brownian motion

The random movement of particles.

Kinetic particle model

Matter is made up of tiny particles that are constantly moving.

Explain diffusion

The net movement of particles from a region of high concentration to a region of low concentration. Diffusion is a passive process and requires no energy.

States of matter in which diffusion occurs

Liquids and gases.

Effect of smaller relative molecular mass on diffusion rate

Diffuses faster.

Effect of higher temperature on diffusion rate

Diffuses faster because particles have more kinetic energy.

Effect of concentration gradient on diffusion rate

A larger concentration gradient increases the rate of diffusion.

Example of diffusion in everyday life

Smell of perfume spreading through a room.

Reason diffusion does not occur effectively in solids

Particles are fixed in position and cannot move freely.

Factors affecting diffusion rate

Temperature, concentration gradient and relative molecular mass.

Diffusion in gases compared with liquids

Diffusion is faster in gases because particles are further apart and move more quickly.