The Periodic The Periodic Table of The Table of The

ElementsElements

The Periodic TableThe Periodic Table

Arrangement of the known elements Arrangement of the known elements based on atomic number and based on atomic number and chemical and physical properties.chemical and physical properties.

Divided into three basic categories:Divided into three basic categories:MetalsMetalsNonmetalsNonmetalsMetalloidsMetalloids

Basic OrganizationBasic Organization

The periodic table is organized by:The periodic table is organized by:

Atomic structureAtomic structureAtomic numberAtomic numberChemical and Physical PropertiesChemical and Physical Properties

Uses of The Periodic TableUses of The Periodic Table

The periodic table is useful in The periodic table is useful in predicting:predicting:

chemical behavior of the elementschemical behavior of the elements trendstrendsproperties of the elementsproperties of the elements

Atomic Structure ReviewAtomic Structure ReviewAtoms are made of Atoms are made of protonsprotons,,

electronselectrons,, andand neutronsneutrons..

ElementsElements are are atoms atoms of only one of only one type.type.

ElementsElements are identified by the are identified by the atomic numberatomic number (# of protons in (# of protons in nucleus).nucleus).

Energy Levels ReviewEnergy Levels Review

ElectronsElectrons are arranged in a region are arranged in a region around the nucleus called around the nucleus called an an electron cloudelectron cloud.. Energy levels Energy levels are are located within the cloud.located within the cloud.

At least 1 energy level and as many At least 1 energy level and as many as 7 energy levels exist in atoms.as 7 energy levels exist in atoms.

Energy Levels ReviewEnergy Levels Review

Electrons in levels farther away from Electrons in levels farther away from the nucleus have more energy.the nucleus have more energy.

Inner levels will fill first before outer Inner levels will fill first before outer levels.levels.

Energy Levels & Valence Energy Levels & Valence ElectronsElectrons

Energy levels hold a specific amount Energy levels hold a specific amount of electrons:of electrons:

11stst level = up to 2 level = up to 2 22ndnd level = up to 8 level = up to 8 33rdrd level = up to 8 (first 18 elements level = up to 8 (first 18 elements

only)only)

Energy Levels & Valence Energy Levels & Valence ElectronsElectrons

The electrons in the outermost level The electrons in the outermost level are called are called valence electronsvalence electrons..

Determine reactivity - how elements will react Determine reactivity - how elements will react with others to form compoundswith others to form compounds

Outermost level does not usually fill completely Outermost level does not usually fill completely with electronswith electrons

Using the Table to Identify Using the Table to Identify Valence ElectronsValence Electrons

Elements are grouped into vertical Elements are grouped into vertical columns because they have similar columns because they have similar properties. properties.

These are called groups or families.These are called groups or families.Groups are numbered 1-18.Groups are numbered 1-18.

Using the Table to Identify Using the Table to Identify Valence ElectronsValence Electrons

Group numbers can help you Group numbers can help you determine the number of valence determine the number of valence electrons:electrons:Group 1 has 1 valence electron.Group 1 has 1 valence electron.Group 2 has 2 valence electrons.Group 2 has 2 valence electrons.Groups 3–12 are transition metals and Groups 3–12 are transition metals and

have 1 or 2 valence electrons.have 1 or 2 valence electrons.

Using the Table to Identify Using the Table to Identify Valence Electrons cont.Valence Electrons cont.

Groups 13–18 have 10 fewer than Groups 13–18 have 10 fewer than the group number. For example:the group number. For example:

Group 13 has 3 valence electrons.Group 13 has 3 valence electrons.Group 15 has 5 valence electrons.Group 15 has 5 valence electrons.Group 18 has 8 valence electrons.Group 18 has 8 valence electrons.

Elements & ReactivityElements & Reactivity

Reactivity is a chemical property that Reactivity is a chemical property that determines determines how elements will react how elements will react with others to form compoundswith others to form compounds..

Elements & ReactivityElements & Reactivity

What makes an element reactive?What makes an element reactive?● Number of valence electrons each atom Number of valence electrons each atom

hashas● When outer levels are full, atoms are When outer levels are full, atoms are

stable.stable.● When they are not full, they react: When they are not full, they react:

● gain, lose, or share 1 or 2 electrons.gain, lose, or share 1 or 2 electrons.

Elements & ReactivityElements & ReactivityThe most reactive metals are the The most reactive metals are the

elements in Groups 1 and 2. elements in Groups 1 and 2.

Elements in Group 1 need seven more Elements in Group 1 need seven more electrons to fill their outer level. electrons to fill their outer level.

Elements in Group 2 need six more electrons to Elements in Group 2 need six more electrons to fill their outer level.fill their outer level.

These groups are known as the These groups are known as the “givers” because they easily give up “givers” because they easily give up their valence electrons to make a their valence electrons to make a compound.compound.

Elements & ReactivityElements & ReactivityThe most reactive nonmetals are the The most reactive nonmetals are the

elements in Groups 16 and 17.elements in Groups 16 and 17.

Elements in Group 16 only need two more Elements in Group 16 only need two more electrons to fill their outer level.electrons to fill their outer level.

Elements in Group 17 only need one more Elements in Group 17 only need one more electron to fill their outer level. electron to fill their outer level.

These groups are known as the These groups are known as the “takers” because they easily receive “takers” because they easily receive valence electrons to make a valence electrons to make a compound.compound.

Groups Groups Groups run vertically in the periodic Groups run vertically in the periodic

table. table. They are numbered from 1–18.They are numbered from 1–18.Elements in the same groups have Elements in the same groups have

the same number of valence the same number of valence electrons in the outer energy level.electrons in the outer energy level.

Grouped elements behave Grouped elements behave chemically in similar ways.chemically in similar ways.

Group 1: Alkali MetalsGroup 1: Alkali MetalsContains: MetalsContains: MetalsValence Electrons: 1Valence Electrons: 1Reactivity: Very ReactiveReactivity: Very ReactiveProperties: Properties:

solidssolidssoftsoftreact violently with waterreact violently with watershiny shiny low densitylow density

Group 2: Alkaline-Earth Group 2: Alkaline-Earth MetalsMetals

Contains: MetalsContains: MetalsValence Electrons: 2Valence Electrons: 2Reactivity: very reactive, but less Reactivity: very reactive, but less

reactive than alkali metals (Group 1)reactive than alkali metals (Group 1)Properties: Properties:

SolidsSolidsSilver coloredSilver coloredMore dense than alkali metalsMore dense than alkali metals

Groups 3-12 Transition Groups 3-12 Transition MetalsMetals

Contain: MetalsContain: MetalsValence electrons: 1 or 2Valence electrons: 1 or 2Reactivity: less reactive than alkali Reactivity: less reactive than alkali

and alkaline-earth metalsand alkaline-earth metalsProperties:Properties:

Higher densityHigher densityGood conductors of heat and electricityGood conductors of heat and electricity

Groups 3-12 Transition MetalsGroups 3-12 Transition MetalsBelow Main TableBelow Main Table

Contain: The Lanthanide and Actinide Contain: The Lanthanide and Actinide SeriesSeriesThese two rows are pulled out of These two rows are pulled out of

sequence and placed below the main sequence and placed below the main table to keep the table from being too table to keep the table from being too wide.wide.

Lanthanides are #’s 58–71.Lanthanides are #’s 58–71.Actinides are #’s 90–103.Actinides are #’s 90–103.

Groups 3-12 Rare Earth Groups 3-12 Rare Earth Elements ~ LanthanidesElements ~ Lanthanides

Lanthanides follow the transition Lanthanides follow the transition metal # 57 Lanthanum in Period 6.metal # 57 Lanthanum in Period 6.

Valence electrons: 3Valence electrons: 3Reactivity: Very reactiveReactivity: Very reactiveProperties:Properties:

● High luster, but tarnish easily High luster, but tarnish easily ● High conductivity for electricityHigh conductivity for electricity● Very small differences between themVery small differences between them

Groups 3-12 Rare Earth Groups 3-12 Rare Earth Elements ~ ActinidesElements ~ Actinides

Actinides follow the transition metal Actinides follow the transition metal # 89 Actinium in Period 7# 89 Actinium in Period 7

Valence electrons: 3 (but up to 6)Valence electrons: 3 (but up to 6)Reactivity: unstableReactivity: unstable

All are radioactiveAll are radioactiveMost made in laboratoriesMost made in laboratories

Metalloids Metalloids A zig-zag line that separates metals A zig-zag line that separates metals

from metalloidsfrom metalloidsElements from Groups 13–17 contain Elements from Groups 13–17 contain

some metalloids.some metalloids.

These elements have characteristics These elements have characteristics of metals and nonmetals.of metals and nonmetals.

Group 13: Boron GroupGroup 13: Boron Group

Group 13: Boron GroupGroup 13: Boron GroupContains: 1 metalloid and 4 metalsContains: 1 metalloid and 4 metalsValence Electrons: 3Valence Electrons: 3Reactivity: ReactiveReactivity: ReactiveOther shared properties:Other shared properties:

Solid at room temperatureSolid at room temperature

Group 14: Carbon GroupGroup 14: Carbon Group

Contains: 1 non-metal, 2 metalloids, Contains: 1 non-metal, 2 metalloids, and 3 metalsand 3 metals

Valence Electrons: 4Valence Electrons: 4Reactivity: VariesReactivity: VariesOther shared properties: Other shared properties:

Solid at room temperatureSolid at room temperature

Group 15: Nitrogen GroupGroup 15: Nitrogen Group

Contains: 2 non-metals, 2 metalloids, Contains: 2 non-metals, 2 metalloids, and 1 metaland 1 metal

Valence electrons: 5Valence electrons: 5Reactivity: VariesReactivity: VariesOther shared properties: Other shared properties:

All but N are solid at room temperature All but N are solid at room temperature

Group 16: Oxygen GroupGroup 16: Oxygen Group

Contains: 3 non-metals, 1 metalloid, Contains: 3 non-metals, 1 metalloid, and 2 metalsand 2 metals

Valence Electrons: 6Valence Electrons: 6Reactivity: ReactiveReactivity: ReactiveOther shared properties: Other shared properties:

All but O are solid at room temperature. All but O are solid at room temperature.

Groups 17 : HalogensGroups 17 : Halogens

Contain: NonmetalsContain: NonmetalsValence Electrons: 7Valence Electrons: 7Reactivity: Very reactiveReactivity: Very reactiveOther shared propertiesOther shared properties

● Poor conductors of electric currentPoor conductors of electric current● React violently with alkali metals to form React violently with alkali metals to form

saltssalts● Never found uncombined in natureNever found uncombined in nature

Group 18 Noble GasesGroup 18 Noble Gases

Contains: NonmetalsContains: NonmetalsValence Electrons: 8 (2 for He)Valence Electrons: 8 (2 for He)Reactivity: Unreactive (least reactive Reactivity: Unreactive (least reactive

group)group)Other shared properties: Other shared properties:

Colorless, odorless gases at room Colorless, odorless gases at room temperaturetemperature

Outermost energy level fullOutermost energy level fullAll found in atmosphereAll found in atmosphere

Hydrogen Stands ApartHydrogen Stands Apart

H is set apart because its properties H is set apart because its properties do not match any single group.do not match any single group.

Valence electrons: 1Valence electrons: 1Reactivity: very, but loses the 1 Reactivity: very, but loses the 1

electron easilyelectron easilyProperties:Properties:

Similar to those of non-metals rather Similar to those of non-metals rather than metals than metals

PeriodsPeriodsPeriods run horizontally across the Periods run horizontally across the

Periodic TablePeriodic TablePeriods are numbered 1Periods are numbered 1––77All the elements in a period will have All the elements in a period will have

the same number of energy levels, the same number of energy levels, which contain electrons. Examples:which contain electrons. Examples:Period 1 atoms have 1 energy level.Period 1 atoms have 1 energy level.Period 2 atoms have 2 energy levels.Period 2 atoms have 2 energy levels.Period 5 atoms have 5 energy levels.Period 5 atoms have 5 energy levels.

Periods ContinuedPeriods ContinuedMoving from left to right across a Moving from left to right across a

period, each element has one more period, each element has one more electron in the outer shell of its atom electron in the outer shell of its atom than the element before it. than the element before it.

This leads to a fairly regular pattern of This leads to a fairly regular pattern of change in the chemical behavior of the change in the chemical behavior of the elements across a period.elements across a period.