1. Chapter 4 Elements Compounds and Mixtures Section 1 Elements

2. ELEMENT Definition: An element is a pure substance that cannot be separated into simpler substances by physical or chemical means Grinding-heating Electrolysis-filtering

3. PURE SUBSTANCE Definition of a pure substance: A pure substance is a substance in which there is only one type of particle Because elements are pure substances, each element only contains one type of particle

4. PURE SUBSTANCE The particles of a pure substance are alike no matter where the substance is found Example: an iron skillet and a meteorite have the same type of particle (iron) in them

5. ELEMENTS Have characteristic properties that do not depend on the amount of material that is present in the sample Elements are classified by their properties. They are grouped into categories according to their shared properties. If you know the category, you know the element.

6. Elements are Grouped into 3 Categories Metals ( Copper) Nonmetals (neon) Metalloids (silicon)

7. Properties of Metals Shiny Conduct electric current Conduct heat energy Examples: tin,copper, iron, lead

8. Properties of Nonmetals Dull Poor conductors of electricity Poor conductors of thermal energy Brittle Not malleable Example: neon, iodine, sulfur

9. Metalloids(Semi Conductors) Have properties of both metals and nonmetals Some shiny some dull Somewhat malleable and ductile Some conduct thermal energy and electric current well Example: silicon, boron and antimony

10. Characteristic Properties Physical: such as melting point, boiling point, density, texture, color Chemical: such as reactivity with acid or oxygen and flammability Electrolysis to separate water