What are the properties of mixtures?

Characteristic properties of mixtures include: 

• No fixed composition – there could be any number of components present in any proportion
• Properties of the individual components are retained
• Individual components can be separated easily by a number of simple procedures
• No energy is used or produced in the formation 
• No fixed melting points or boiling points 

Most common examples of mixtures:

• Sea water – mixture of water and salt
• Air – mixture of oxygen, nitrogen, carbon dioxide and other gases
• Smog – mixture of smoke and fog
• Brass – mixture of copper and zinc
• Cement – mixture of sand, gravel and water