Metals, Nonmetals and Metalloids Coloring in the Periodic Table Notice the difference between the appearance of the metals and nonmetals. Click here for a better view of each of the elements. Physical properties of METALS • Metals are SOLIDS at room temperature. (except mercury) • Metals are HARD. (except Lithium, Potassium, Sodium) Physical Properties of METALS Metals are shiny. (Have “luster”) LUSTER – the way an object’s surface reflects light When you leave a spoon in a cup of hot drink, the bit poking out of the drink gets hot. Why? Conduction! METALS are the best conductors of heat. This is because the electrons in metals move more freely than in non-metals, allowing the heat energy to travel across the metal. For example, when the spoon touches the hot drink, the heat from the drink excites the electrons in the metal, and the electrons transfer the energy from one electron to another, carrying the heat all the way up the spoon quickly. Best conductors: silver and copper Physical Properties of METALS • Metals are good conductors of electricity. Copper, silver, and gold are good electrical conductors. In a conductor, electric current can flow freely. Since metals have free electrons, they can carry a charge easily. Copper Wiring Physical Properties of METALS Metals are malleable (bendable). Ex. Aluminum Foil Physical Properties of METALS Metals are ductile. Ductility or ductile – can be drawn (pulled) into a wire NONMETALS To the right on the PT (except Hydrogen) Non metals may be solids, liquids or gases. Examples: Solids – Carbon, Sulfur, Phosphorus Liquid – Bromine Gases – Oxygen, Hydrogen, Nitrogen Physical Properties of NONMETALS Nonmetals have a dull luster. (They are not shiny!) Example: Phosphorus Physical Properties of NONMETALS Nonmetals are insulators. They do not conduct electricity or heat well. The atoms in nonmetals do not have loose electrons. Therefore, when electricity, or something hot touches a non-metal, the energy does not move quickly through the material. What would you rather stir a hot pot with—a wooden spoon or a metal spoon? Physical Properties of NONMETALS Nonmetals are soft and brittle (fragile). Example: Sulfur An interesting element: Carbon Ever break the point of your pencil? That’s because it’s made of graphite, a substance made up completely of Carbon—a brittle nonmetal. However diamonds, the hardest material of all, are made of the same element: Carbon. Look at how the carbon atoms are arranged in diamonds—why do you think diamonds are harder than graphite? Carbon atoms in graphite METALLOIDS Metalloids are found along the stairstep. METALLOIDS • Elements classified as Metalloids have physical properties of both metals and non-metals. • Some are shiny, some are dull, they are somewhat malleable and ductile, and can conduct heat and electricity at a lesser level than metals. SILICON BORON ARSENIC METALLOIDS • Some metalloids are useful semiconductors, which are used in electronics (radio, computer chips, telephones, etc.) • They are useful because they conduct just the right amount of electricity or heat.