Electron Dot Structures & Electron Dot Structures & MetalsMetals

Chapter 17 & 19Chapter 17 & 19

Electron Dot DiagramsElectron Dot Diagrams

Elements that are in the same group have Elements that are in the same group have the same number of electrons in their the same number of electrons in their outer energy level.outer energy level.

These outer electrons are so important in These outer electrons are so important in determining the chemical properties of an determining the chemical properties of an element that a special way to represent element that a special way to represent them has been developed.them has been developed.

Electron Dot DiagramsElectron Dot Diagrams An An electron dot diagramelectron dot diagram

uses the symbol of the uses the symbol of the element and dots to element and dots to represent the electrons in represent the electrons in the outer energy level. the outer energy level.

Electron dot diagramsElectron dot diagrams are are used also to show how used also to show how the electrons in the outer the electrons in the outer energy level are bonded energy level are bonded when elements combine when elements combine to form compounds. to form compounds.

Same Group—Similar PropertiesSame Group—Similar Properties

The elements in The elements in Group 17, the Group 17, the halogens, have halogens, have electron dot diagrams electron dot diagrams similar to chlorine. similar to chlorine.

All halogens have All halogens have seven electrons in seven electrons in their outer energy their outer energy levels. levels.

Same Group—Similar PropertiesSame Group—Similar Properties

A common property of the A common property of the halogens is the ability to halogens is the ability to form compounds readily form compounds readily with elements in Group 1.with elements in Group 1.

The Group 1 element, The Group 1 element, sodium, reacts easily with sodium, reacts easily with the Group 17 element, the Group 17 element, chlorine.chlorine.

The result is the The result is the compound sodium compound sodium chloride, or NaCl—chloride, or NaCl—ordinary table salt. ordinary table salt.

Same Group—Similar PropertiesSame Group—Similar Properties

Not all elements will Not all elements will combine readily with combine readily with other elements. other elements.

The elements in Group The elements in Group 18 have complete outer 18 have complete outer energy levels.energy levels.

This special configuration This special configuration makes Group 18 makes Group 18 elements relatively elements relatively unreactiveunreactive

Properties of MetalsProperties of Metals

In the periodic table, In the periodic table, metals are elements metals are elements found to the left of the found to the left of the stair-step linestair-step line

Properties of MetalsProperties of Metals

MetalsMetals usually have usually have common propertiescommon properties

they are good they are good conductors of heat conductors of heat and electricity, and electricity,

and all but one are and all but one are solid at room solid at room temperature.temperature.

Metals also reflect light. This is a property Metals also reflect light. This is a property called luster.called luster.

Metals are Metals are malleablemalleable (MAL yuh bul), (MAL yuh bul), which means they can be hammered or which means they can be hammered or rolled into sheets.rolled into sheets.

Metals are also Metals are also ductileductile, which means they , which means they can be drawn into wires.can be drawn into wires.

Properties of MetalsProperties of Metals

The Alkali MetalsThe Alkali Metals

The elements in Group 1 The elements in Group 1 of the periodic table are of the periodic table are the alkali (AL kuh li) the alkali (AL kuh li) metals.metals.

Group 1 metals are shiny, Group 1 metals are shiny, malleable, and ductile.malleable, and ductile.

They are also good They are also good conductors of heat and conductors of heat and electricity. However, they electricity. However, they are softer than most other are softer than most other metals.metals.

The Alkali MetalsThe Alkali Metals

The alkali metals are the most reactive of The alkali metals are the most reactive of all the metals. They react all the metals. They react rapidlyrapidlysometimes violentlysometimes violentlywith oxygen with oxygen and water.and water.

Alkali metals don’t occur in nature in their Alkali metals don’t occur in nature in their elemental form and are stored in elemental form and are stored in substances that are unreactive, such as substances that are unreactive, such as an oil. an oil.

The Alkali MetalsThe Alkali Metals

Each atom of an alkali metal has one Each atom of an alkali metal has one electron in its outer energy level.electron in its outer energy level.

This electron is given up when an alkali This electron is given up when an alkali metal combines with another atom.metal combines with another atom.

As a result, the alkali metal becomes a As a result, the alkali metal becomes a positively charged ion in a compound such positively charged ion in a compound such as sodium chloride.as sodium chloride.

The Alkaline Earth MetalsThe Alkaline Earth Metals Each atom of an alkaline Each atom of an alkaline

earth metal has two earth metal has two electrons in its outer electrons in its outer energy level.energy level.

The alkaline earth metals The alkaline earth metals make up Group 2 of the make up Group 2 of the periodic table.periodic table.

These electrons are given These electrons are given up when an alkaline earth up when an alkaline earth metal combines with a metal combines with a nonmetal.nonmetal.

Fireworks and Other UsesFireworks and Other Uses As a result, the alkaline As a result, the alkaline

earth metal becomes a earth metal becomes a positively charged ion in a positively charged ion in a compound such as compound such as calcium fluoride, CaF2.calcium fluoride, CaF2.

Magnesium metal is one Magnesium metal is one of the metals used to of the metals used to produce the brilliant white produce the brilliant white color in fireworks.color in fireworks.

Compounds of strontium Compounds of strontium produce the bright red produce the bright red flashes.flashes.

Transition ElementsTransition Elements

Transition elementsTransition elements are those elements in are those elements in Groups 3 through 12 in the periodic table. Groups 3 through 12 in the periodic table.

They are called transition elements because They are called transition elements because they are considered to be elements in transition they are considered to be elements in transition between Groups 1 and 2 and Groups 13 through between Groups 1 and 2 and Groups 13 through 18. 18.

Transition elements are familiar because they Transition elements are familiar because they often occur in nature as uncombined elements. often occur in nature as uncombined elements.

Transition ElementsTransition Elements

Transition elements Transition elements often form colored often form colored compounds.compounds.

Gems show brightly Gems show brightly colored compounds colored compounds containing chromiumcontaining chromium

Iron, Cobalt, and NickelIron, Cobalt, and Nickel

The first elements in The first elements in Groups 8, 9, and Groups 8, 9, and 1010iron, cobalt, and iron, cobalt, and nickelnickelform a unique form a unique cluster of transition cluster of transition elementselements

These three sometimes These three sometimes are called the iron triad. are called the iron triad.

All three elements are All three elements are used in the process to used in the process to create steel and other create steel and other metal mixtures. metal mixtures.

Copper, Silver, and GoldCopper, Silver, and Gold

Copper, silver, and goldCopper, silver, and goldthe the three elements in Group three elements in Group 1111are so stable that they can are so stable that they can be found as free elements in be found as free elements in nature. nature.

These metals were once used These metals were once used widely to make coins. widely to make coins.

For this reason, they are For this reason, they are known as the coinage metalsknown as the coinage metals

Copper often is used in Copper often is used in electrical wiring because of its electrical wiring because of its superior ability to conduct superior ability to conduct electricity and its relatively low electricity and its relatively low cost. cost.