Elements – More then just a weird looking car

Elements  A pure substance that cannot be separated into simpler substances by physical or chemical means  All elements are made from particles of matter  Each element only contains one type of particle  Elements cannot be changed into anything else

Identifying Elements  Each element can be identified by its unique set of properties  Can use physical or chemical properties  Examples: boiling point, melting point, density, color, hardness, texture

Classifying Elements by their Properties  Three main categories of elements  Metals – Shiny and conduct heat energy and electric current  Nonmetals – Dull and do not conduct heat energy or electric current  Metalloids – have properties of both metals and nonmetals

Compounds  A pure substance composed of two or more elements that are chemically combines  Involves a chemical change  Each compound has its own physical and chemical properties  Compounds are new pure substances different from the elements that make it up

Mixtures  A combination of two or more substances that are not chemically combined  No reaction or change takes place  Example is a pizza. Cheese and tomato sauce do not react when put together  Each substance in a mixture keeps its identity  Mixtures involve physical changes only

Solutions  A mixture that appears to be a single substance  Composed of particles of two or more substances that are distributed evenly among each other  Process of spreading evenly is called dissolving  Solute is the substance that is dissolved  Solvent is the substance in which the solute is dissolved