States of Matter: Solids, Liquids and Gases

Objective

State the distinguishing properties of solids, liquids and gases.

Properties of Solids

Solids have a definite shape and a definite volume. Their particles are closely packed in a fixed arrangement and vibrate about fixed positions.

• Definite Shape
• Definite Volume
• Particles are closely packed
• Particles vibrate about fixed positions
• High density
• Incompressible (difficult to change volume)

Properties of Liquids

Liquids have a definite volume but no definite shape. They take the shape of the container they are in. Their particles are close together but can move past each other.

• Indefinite Shape
• Definite Volume
• Particles are close together but can move past each other
• Relatively high density
• Slightly compressible

Properties of Gases

Gases have no definite shape and no definite volume. They expand to fill the entire volume of their container. Their particles are far apart and move randomly.

• Indefinite Shape
• Indefinite Volume
• Particles are far apart and move randomly
• Low density
• Highly compressible

Comparison of Solids, Liquids and Gases

Property	Solids	Liquids	Gases
Shape	Definite	Indefinite	Indefinite
Volume	Definite	Definite	Indefinite
Particle Arrangement	Fixed, close together	Close together, can move past each other	Far apart, random motion
Particle Motion	Vibrate about fixed positions	Move past each other	Random, rapid motion
Density	High	Relatively high	Low
Compressibility	Incompressible	Slightly compressible	Highly compressible