Metals, Nonmetals and Metalloids

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. (except mercury) Metals are HARD. (except Lithium, Potassium, Sodium) Metals are found to the left of the zig- zag line.

Physical Properties of METALS Metals have shiny luster. (or metallic luster) LUSTER – the way an object’s surface reflects light

Best conductors: silver and copper 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. Metals have few electrons in their outer energy level. 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. A conductor is something that lets heat and electricity go through it. 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. Malleable or Malleability - metals ability to be shaped or formed as by hammering or pressure; can be beaten into thin sheets Aluminum is malleable.

Physical Properties of METALS Metals are ductile. Ductility or ductile – can be drawn into a wire

Non metals may be solids, liquids or gases. Examples of NONMETALS 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 which means that they do not let heat and electricity go through it easily. 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. They have almost a complete set of electrons in their outer energy level.

Physical Properties of NONMETALS Nonmetals are soft (except for diamonds and brittle. 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. Carbon atoms in graphite 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? You may also want to discuss how we are using carbon to create new materials such as nanotubes, or discuss buckeyballs.

The elements contained in the classification of Metalloids: Metalloids have ½ complete set of electrons in outer energy level.

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 ARSENIC BORON

METALLOIDS Some metalloids are useful semiconductors, which are used in electronics (radio, computers, telephones, etc.) Semiconductor: a material which has properties between conductors and insulators They are useful because they conduct just the right amount of electricity or heat.

Where do we find METALS? Some metals like gold, silver, and platinum are found as pure substances in the earth’s crust because they are least reactive. Most metals are reactive and are found as oxides (react with oxygen), carbonates (react with carbon), sulfides (react with sulfur). Minerals : are elements or compounds which occur naturally inside the earth’s crust. Ore : is a mineral from which metals can be extracted profitably.