The Periodic Table

The Periodic TableUnit 5Chapter 5

Play Me 1Play Me 2Organizing the elementsDimitri Mendeleev

Henry Moseley

Glenn Seaborg

I. Dimitri MendeleevArranged elements in order of increasing atomic massPlaced elements with similar properties in columnsPredicted the existence of unknown elements

Bonus Russian chemistBonus Published his first periodic table in 1872

Mendeleevs Periodic Table in RussianII. Henry MoseleyDefined the atomic number (1911)Arranged the elements according to their atomic numberDeveloped the modern periodic table based on the periodic law.

Bonus English PhysicistIII. The Periodic LawThe physical and chemical properties of the elements are periodic functions of their atomic numbers.

Periodically, due to the elements properties, a new row is started.(Mendeleev)

Elements are in order of atomic number.(Moseley)Bonus: Glenn SeaborgAmerican Nuclear ChemistPredicted the Actinide series (elements 89-102) in 1944Worked on the Manhattan Atomic Bomb ProjectDiscovered many new radioactive elements

The Modern Periodic TableGroups and periods

Metals, nonmetals, and metalloids

Periodic trends

I. Groups (columns)There are 18 groups, 8 are known as representative groups (A columns)Elements in a group have similar propertiesGroups are also called families

124356789101112131415161718 Groups

1A2A3A4A5A6A7A8ARepresentative GroupsII. Periods (rows)There are 7 periodsThe First element in a period is a very reactive metalThe last element in a period is an unreactive nonmetal

Periods

1234567Very reactive metal(hydrogen is not a metal)Very unreactivce nonmetalIII. MetalsAre located to the left of the zigzag line

51 Sb52 Te33 As32 Ge14 Si5 B85 At84 PoB. Properties of metalsMost are shiny silver or gray in color

Good conductors of heat and electricity

Ductile: can be drawn out into wires

High melting points

Malleable

Almost all are solid at room temperature

IV. NonmetalsAre located to the right of the zigzag line

51 Sb52 Te33 As32 Ge14 Si5 B85 At84 Po7 NElements in NonmetalsDull and different colors

Poor conductors of heat and electricity

Low melting points

Brittle

Can be found as solid, liquid, or gas at room temperature. (many are gas)B. Properties of nonmetals

V. MetalloidsBorder the zigzag lineHave properties of both metals and nonmetalsUsed as semiconductors in electronics

51 Sb52 Te33 As32 Ge14 Si5 B85 At84 Po5 BElements in Metalloids

VI. Periodic TrendsValence ElectronsElectrons in the outer energy levelRepresentative elements left to right: 1, 2, 3, 4, 5, 6, 7, 8

valence electronThis atom has how many valence electrons?4

12345678Representative Group Valence ElectronsOxidation numbersCharge of the ion formedRepresentative elements from left to right: +1, +2, +3, (+/-) 4, -3, -2, -1, 0Why? - Atoms with 8 e- in the outer energy level are STABLE. (except first energy level)Bromine ion

Hey, I gained one e-. My charge and oxidation number are both -1

+1+2+3+/-4-3-2-10Representative Group Oxidation NumbersC. Size of the atomsSize decreases from left to right due to more attractive forceslithiumboronnitrogenfluorine3 p+ 3 e-5 p+ 5 e-7 p+ 7 e-9 p+ 9 e-2. Size increases from top to bottom due to more occupied energy levelshydrogenlithiumsodium1 occupied energy level2 occupied energy levels3 occupied energy levelsSize Trends of the Elements

Element Groupings

I. Alkali MetalsGroup 1A on the periodic tableAre extremely reactiveHave one valence electronReactivity increases from top to bottom.

II. Alkaline Earth MetalsGroup 2A on the periodic tableAre moderately reactiveHave two valence electronsCa and Mg are important biologically in construction and transportation

III. Transition MetalsFound between groups 2A and 3AProperties varyForm brightly colored compounds

IV. Boron FamilyGroup 3A on the periodic tableMembers have 3 valence electronsAluminum is the most abundant metal on Earth. Third overall.

V. Carbon FamilyGroup 4A on the periodic tableMembers have 4 valence electronsCarbon containing compounds drive life on earth. (organic)Si is the 2nd most abundant element on earth

VI. Nitrogen FamilyGroup 5A on the periodic tableMembers have 5 valence electronsNitrogen is the most abundant element in the earths atmosphere N and P are essential for plant growth

VII. Oxygen FamilyGroup 6A on the periodic tableMembers have 6 valence electronsOxygen combines with metals to form oxides (rust). It is moderately reactive.Most abundant element on earth is oxygen.

VIII. Halogens (salt formers)Group 7A on the periodic tableMembers have 7 valence electronsCombine with metals to form saltsMost reactive of the nonmetalsReactivity decreases from top to bottom.

IX. Noble GasesGroup 8A on the periodic tableMembers have 8 valence electrons (except He).Are extremely nonreactive or inertAre odorless and colorless

X. Rare Earth ElementsLanthanide Series- elements 57-70Actinide Series- elements 89-102Many are not natural and radioactive

Thats All Folks

MetalsAre located to the left of the zigzag line

51 Sb52 Te33 As32 Ge14 Si5 B85 At84 PoB. Properties of metalsMost are shiny silver or gray in color

Good conductors of heat and electricity

Ductile: can be drawn out into wires

High melting points

Malleable

Almost all are solid at room temperature

NonmetalsAre located to the right of the zigzag line

51 Sb52 Te33 As32 Ge14 Si5 B85 At84 Po7 NElements in NonmetalsDull and different colors

Poor conductors of heat and electricity

Low melting points

Brittle

Can be found as solid, liquid, or gas at room temperature. (many are gas)B. Properties of nonmetals

MetalloidsBorder the zigzag lineHave properties of both metals and nonmetalsUsed as semiconductors in electronics

51 Sb52 Te33 As32 Ge14 Si5 B85 At84 Po5 BElements in Metalloids