Chapter 3, Section 3Metals

Monday, November 16, 2009

Pages 89 -- 94

Objectives

Describe chemical and physical properties of metals.

Identify and describe different kinds of metals, and compare the properties of the various families of metals.

Vocabulary Words

Malleable

Ductile

Conductor

Magnetic

Corrosion

Alloy

Alkali metal

Alkaline earth metal

Transition metal

Lanthanide

Actinide

What is a Metal?

Metals can be classified according to the following physical properties:– Hardness– Shininess– Malleability– Ductility

Malleable Metal

A malleable metal is a metal than can be pounded into shapes.

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Metals

Metals are good conductors.– Transmits heat and

electricity easily.

Metals show a wide variety of chemical properties.– Some are reactive

and some are unreactive.

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Alloys

A mixture of metals is called an alloy.

Useful alloys combine the best properties of two or more metals in a single substance.

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Metals in the Periodic Table

The metals in a group, or family, have similar properties, and these family properties change gradually as you move across the table.

Alkali Metals

Alkali metals are the most reactive metals of all.They are never found uncombined in nature (only in compounds).Most reactive because these elements have atoms with one valence electron that is easily transferred to other atoms during a chemical change.2 most important alkali metals are sodium and potassium.

Alkaline Earth Metals

Not as reactive as the metals in Group 1.

More reactive than most metals.

Never found uncombined in nature.

Each is fairly hard, gray-white, and good conductors.

Most common are magnesium and calcium.

Each atom of an alkaline metal has 2 valence electrons.

Transition Metals

The elements in Groups 3 through 12 are called the transition metals.Transition metals form a bridge between the very reactive metals on the left side to the less reactive metals on the right.Examples include iron, copper, nickel, silver, and gold.Most are shiny and hard.They are all good conductors of electricity.The are fairly stable and reacts slowly or not at all with air and water.

Metals in Mixed Groups

Metals in Mixed Groups are located in Groups 13 through 16.

Metals in mixed group include metals, nonmetals, and metalloids.

Not reactive.

Examples include aluminum, tin, and lead.

Lanthanides and Actinides

Lanthanides and Actinides are located at the bottom of the periodic table.

These elements are rare earth elements.

These elements fit in periods 6 and 7 between the alkaline earth metals and the transition metals.

Only located at the bottom for convenience.

Lanthanides

Lanthanides are soft, malleable, shiny metals.

Lanthanides are highly conductive.

Used to make various alloys.

Usually found with other lanthanides in nature.

Difficult to separate.

Actinides

Only a small portion of actinides exist on Earth in any significant amounts.Most elements after uranium in the periodic table were created artificially.The nuclei are very unstable (breaks apart quickly).So unstable that many of these synthetic elements last for only a fraction of a second after they are made.

Homework

Workbook 3.3 due 11/18

Vocabulary Quiz 3.3 on 11/18