Liquids and Solids

Liquids

Objectives• Identify and explain the properties of liquids

according to the Kinetic Molecular Theory• Describe the process in which liquids turn to gases.• Describe the process in which liquids turn to solids

Properties of Liquids• Definite Volume• No definite shape• Less K.E. than gases• Intermolecular forces hold

particles together• Constant motion of particles

allows liquids to flow.• Gases and liquids are both

fluids

Liquids• Liquids are the least

common state of matter in the universe.

• Substances exist in the liquid phase in a narrow window of temperatures.

Liquids• High density

• Particles are close together

• Most substances are slightly less dense in the liquid state as compared to the solid state

• Densities of liquid substances vary.

Liquids• Relatively incompressible

• Particles are close together.• Able to readily diffuse.

• Constant motion of particles• Diffusion of liquids is slower than for gases due to

the particles being close togetherAnimation: How Diffusion Works

Liquids• Surface tension – a

force that pulls adjacent parts of a liquid’s surface together, resulting in the smallest possible surface area

• Capillary action is a closely relate property

Evaporation and Boiling• Vaporization – process in

which a liquid turns to a gas• evaporation –

vaporization that occurs below the boiling point

• Boiling – occurs at the boiling point.

Formation of Solids• Freezing – change from a

liquid to a solid• Low kinetic energy results

in particles being more attracted to each other and the formation of a more ordered structure