Hazard Symbols Changes of state 1. There are three states of matter – solids, liquids and gases 2. When a substance changes state, the particles gain or lose energy 3. Melting – solid into liquid (gain) 4. Freezing – liquid into solid (lose) 5. Boiling – liquid into gas (gain) 6. Condensing – gas into liquid (lose) Changes of State - Warming Changes of State - Cooling Element, Compound, Mixture 1. An element is a substance which contains only one type of atom 2. A compound is a substance in which two or more atoms are chemically joined together 3. A mixture contains two or more elements or compounds that are not chemically joined together. Element, Compound, Mixture Separation Techniques 1. The substances in mixtures can be separated physically; compounds cannot be broken down physically Distillation Chromatography Separating Sand and Salt Wordsearch Quiz