Unit 2 Materials and their structure guided notes and practice questions. This unit contains 7 sections. 1. Sort the states of matter into solids, liquids and gases.                 2. Learn about the properties of solids, liquids and gases.                 3. Use the particle theory to describe the structure of solids, liquids and gases.      4. Use the particle theory to learn about the properties of solids, liquids and gases.  5