Elements Chapter 3, Section 1 p. 56 - 59 Vocabulary: element pure substance metal nonmetal metalloid Neon gas is used to make this sign glow

Elements p. 55 1. A substance that cannot be separated or broken down into simpler substances by chemical means. Elements p. 55 Why is this not an element? Elements are pure substances in which there is only one type of particle. Water has both oxygen and hydrogen in it. Each element contains only one type of particle. The particles of an element are alike no matter where they are found. Hydrogen Oxygen

Pure Substance A sample of matter, either a single element or a single compound, that has definite chemical and physical properties. Examples of pure substances Silver Gold Copper

Properties of Elements Each element can be identified by its unique set of properties, called characteristic properties. Characteristic properties do not depend on how much of the element is present. Characteristic properties can include physical properties such as boiling point, melting point, density, color, texture, and hardness. They can also include chemical properties such as flammability and reactivity. Melting point: 1,495°C Density: 8.9g / cm³ Unreactive with oxygen in the air Melting point: 1,535°C Density: 7.9 g / cm³ Combines slowly with oxygen in the air to form rust Melting point: 1,455°C Density 8.9 g/ cm³ Unreactive with oxygen in the air

Classifying Elements by Their Properties Elements are grouped into three categories by the properties they share. The three major categories are metals, nonmetals, and metalloids. 3. metal – an element that is shiny and conducts heat and electricity well – example: platinum 4. nonmetal – an element that conducts heat and electricity poorly – example: neon 5. metalloid – an element that has properties of both metals and nonmetals – example: boron

Metals Lead Copper Tin Metals are elements that are shiny and are good conductors or heat and electric current. They are malleable (they can be hammered into thin sheets). They are also ductile (they can be drawn into thin wires).

Nonmetals Nonmetals are elements that are dull (not shiny) and Iodine Neon Sulfur Nonmetals are elements that are dull (not shiny) and that are poor conductors of heat and electric current. Solids tend to be brittle and unmalleable. Few familiar objects are made only of nonmetals.

Metalloids Metalloids are also called semiconductors. They have Silicon Boron Antimony Metalloids are also called semiconductors. They have properties of both metals and nonmetals. Some metalloids are shiny. some are dull. Metalloids are somewhat malleable and ductile. Some metalloids conduct heat and electric current as well.

Meet the Elements

Quiz Time Metals, Nonmetals or Metalloids? 1. Why is an element considered to be a pure substance? It contains only one type of particle 2. What are three characteristics of metals? They are shiny, conduct heat energy and conduct electric current. Metals, Nonmetals or Metalloids? 3. These are good conductors of electric current: Metals and some metalloids 4. These are brittle and nonmalleable: Nonmetals 5. These are shiny: Metals 6. These are poor conductors of thermal energy: Nonmetals and some metalloids