Chapter 19Elements and Their

PropertiesSection 1

Metals

Metals Review

Located on left side of Periodic TableDuctile, malleable, good conductors of

heat & electricity1-3 valence electrons – tend to lose

electronsForm ionic bondsMost solids at room temperature (except)Most reflect light = shiny = luster

Metallic Bonding

Like a pot luck dinnerMetallic bonding is the special type of

bonding with positive ions surrounded by a cloud of electrons.

Outer level electrons are not held tightly to the nucleus

Electrons move freely among the positively charge metallic ions

Metallic Bonding ExplainsMetallic Properties

Ductile and malleable – metal doesn’t break because the ions are in layers that slide past each other without losing attraction to the electron cloud

Conduct electricity – outer level electrons weakly held and move freely

Alkali Metals

Group 1 metals – 1 valence electronSofter than most metalsMOST REACTIVE of all metalsReact violently with oxygen and waterMust be stored in unreactive oilsDo NOT occur in nature as elements –

always in compounds

Alkaline Earth Metals

Group 2 metals – 2 valence electrons

Very reactive metals

Do NOT occur in nature as elements – always in compounds

Transition Elements

Groups 3-12 are in transition between groups 1-2 and 13-18

1-3 valence electronsMost familiar metals because they occur

as elements in natureOften form colorful compounds

Inner Transition Metals

Lanthanides # 58-71 (follow lanthanum)

Actinides #90-103(follow actinium)all radioactive and unstable

Transuranium elementselements beyond uranium # 92all synthetic, all radioactive

Chapter 19Elements and Their

PropertiesSection 2

Nonmetals

Nonmetals Review

Located on right side of Periodic Table (except)

NOT ductile, NOT malleableNOT good conductors of electricity and heat5-7 valence electrons – tend to gain or share

electrons. Form ionic or covalent bondsHydrogen can lose 1 or gain 1 electronMost gases at room temperatureNOT shiny

Halogens

Group 17

7 valence electrons

4 nonmetals, 1 metalloid

Fluorine is the MOST chemically active of all elements

The Noble Gases

Group 18

8 valence electrons (except)

Chemically stable

Exist as isolated atoms

No naturally occurring compounds

Chapter 19Elements and Their

PropertiesSection 3

Mixed Groups

Metalloids

Located in the middle of Periodic Table along the staircase

3-7 valence electrons

Can form ionic or covalent bonds

Metallic and nonmetallic properties

Allotropes of Carbon

Allotropes are different forms of the same element with different molecular structures.

Diamonds – each carbon bonded to 4 other carbons in tetrahedrons. Tight crystalline structures

Graphite – each carbon bonded to 3 other carbons in hexagonal layers. 4th electron of each carbon is loosely bonded to the next layer – layers slide past each other – pencils

Buckminsterfullerene – buckyball – carbons bonded in soccer ball shape – 1991 used to create nanotubes

Synthetic Elements

Synthetic elements are manmade elements.

All have 92+ protons except #43 and #61Created by smashing existing elements

with particles. New elements disintegrate to form other

elementsStudying how these elements form and

how they disintegrate, scientists learn more about the forces holding atoms together.