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 Divided into three basic categories:categories:

MetalsMetalsNonmetalsNonmetalsMetalloidsMetalloids

Basic OrganizationBasic Organization

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

Atomic structureAtomic structureAtomic numberAtomic numberChemical and Physical PropertiesChemical and Physical Properties

Uses of The Periodic Uses of The Periodic TableTable

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

chemical behavior of the chemical behavior of the elementselements

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 of only one type.one type.

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

Energy Levels ReviewEnergy Levels Review

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

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

Energy Levels ReviewEnergy Levels Review

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

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

Energy Levels & Valence Energy Levels & Valence ElectronsElectrons

Energy levels hold a specific Energy levels hold a specific amount of electrons:amount 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 level = up to 8 (first 18 elements only)elements only)

Energy Levels & Valence Energy Levels & Valence ElectronsElectrons

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

Determine reactivity - how elements Determine reactivity - how elements will react with others to form will react with others to form compoundscompounds

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

Using the Table to Using the Table to Identify Valence ElectronsIdentify Valence Electrons

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

These are called groups or These are called groups or families.families.

Groups are numbered 1-18.Groups are numbered 1-18.

Using the Table to Using the Table to Identify Valence ElectronsIdentify Valence 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 Groups 3–12 are transition metals and have 1 or 2 valence electrons.and have 1 or 2 valence electrons.

Using the Table to Using the Table to Identify Valence Identify Valence Electrons cont.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 Reactivity is a chemical property that determines property that determines how how elements will react with others elements will react with others to form compoundsto form compounds..

Elements & ReactivityElements & Reactivity

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

● When outer levels are full, atoms When outer levels are full, atoms are stable.are stable.

● When they are not full, they When they are not full, they react: react: ● gain, lose, or share 1 or 2 gain, lose, or share 1 or 2 electrons.electrons.

Elements & ReactivityElements & ReactivityThe most reactive metals are The most reactive metals are the elements in Groups 1 and 2. the 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 Elements in Group 2 need six more electrons to fill their outer level.electrons to fill their outer level.

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

Elements & ReactivityElements & ReactivityThe most reactive nonmetals are The most reactive nonmetals are the elements in Groups 6 and 7.the elements in Groups 6 and 7.

Elements in Group 6 only need two more Elements in Group 6 only need two more electrons to fill their outer level.electrons to fill their outer level.

Elements in Group 7 only need one more Elements in Group 7 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 “takers” because they easily receive valence electrons to receive valence electrons to make a compound.make a compound.

Groups Groups Groups run vertically in the Groups run vertically in the periodic table. periodic table.

They are numbered from 1–18.They are numbered from 1–18.Elements in the same groups Elements in the same groups have the same number of have the same number of valence electrons in the outer valence electrons in the outer energy level.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 Reactivity: very reactive, but less reactive than alkali metals less reactive than alkali metals (Group 1)(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 Reactivity: less reactive than alkali and alkaline-earth metalsalkali and alkaline-earth metals

Properties:Properties:Higher densityHigher densityGood conductors of heat and Good conductors of heat and electricityelectricity

Groups 3-12 Transition Groups 3-12 Transition MetalsMetals

Below Main TableBelow Main TableContain: The Lanthanide and Contain: The Lanthanide and Actinide SeriesActinide SeriesThese 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 table to keep the table from being too wide.too 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 Actinides follow the transition metal # 89 Actinium in Period 7metal # 89 Actinium in Period 7

Valence electrons: 3 (but up to Valence electrons: 3 (but up to 6)6)

Reactivity: unstableReactivity: unstableAll are radioactiveAll are radioactiveMost made in laboratoriesMost made in laboratories

Metalloids Metalloids A zig-zag line that separates A zig-zag line that separates metals from metalloidsmetals from metalloids

Elements from Groups 13–17 Elements from Groups 13–17 contain some metalloids.contain some metalloids.

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

Group 13: Boron GroupGroup 13: Boron Group

Group 13: Boron GroupGroup 13: Boron GroupContains: 1 metalloid and 4 Contains: 1 metalloid and 4 metalsmetals

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

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

Solid at room temperatureSolid at room temperature

Group 15: Nitrogen Group 15: Nitrogen GroupGroup

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

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

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

Group 16: Oxygen GroupGroup 16: Oxygen Group

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

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

All but O are solid at room All but O are solid at room temperature. 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 Poor conductors of electric currentcurrent

● React violently with alkali metals React violently with alkali metals to form saltsto form salts

● 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 Reactivity: Unreactive (least reactive group)reactive 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 H is set apart because its properties do not match any properties do not match any single group.single group.

Valence electrons: 1Valence electrons: 1Reactivity: very, but loses the Reactivity: very, but loses the 1 electron easily1 electron easily

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

PeriodsPeriodsPeriods run horizontally across Periods run horizontally across the Periodic Tablethe Periodic Table

Periods are numbered 1Periods are numbered 1––77All the elements in a period will All the elements in a period will have the same number of energy have the same number of energy levels, which contain electrons. levels, which contain electrons. Examples: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 Moving from left to right across a period, each element has one a period, each element has one more electron in the outer shell more electron in the outer shell of its atom than the element of its atom than the element before it. before it.

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