Metals, Nonmetals and Metalloids

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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. All Metals are SOLIDS . (except mercury) - PowerPoint PPT Presentation

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Metals, Nonmetalsand 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

• All Metals are SOLIDS. (except mercury)

• Most Metals are HARD. (except Lithium, Potassium, Sodium)

Physical Properties of METALS

Metals have shiny luster. (or metallic luster)

LUSTER – the way an object’s surface reflects light

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 METALSMetals 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

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. 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 (except for diamonds) and brittle.

Example: Sulfur

An interesting element: CarbonEver 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?

METALLOIDSThe elements contained in the classification of Metalloids:

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.

BORONSILICON ARSENIC

METALLOIDS• Some metalloids are useful semiconductors,

which are used in electronics (radio, computers, telephones, etc.)

• 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.