Notes ? Matter Describing Matter Definition - Anything that has mass and takes up space. Matter can be in three states (plasma is another state but exists at high energy that we will not deal with) Solid ? definite shape, definite volume, particles packed closely together Liquid ? indefinite shape, definite volume, particles can flow easily Gas/Vapor ? indefinite shape, indefinite volume, particles are spaced far apart Similar terms but not interchangeable Gases exist as gases at room temperature Vapors are in a gaseous state but generally exist as solids or liquids Characteristic/Physical Properties Physical Properties ? characteristics that are observed but never change for a substance Boiling point (condensation) - temperature at which a liquid turns to a vapor