Mendeleev’s Periodic TableMendeleev’s Periodic Table

Dmitri Mendeleev

Modern Russian TableModern Russian Table

Stowe Periodic TableStowe Periodic Table

A Spiral Periodic TableA Spiral Periodic Table

““Mayan” Mayan” Periodic Periodic

TableTable

The Periodic TableThe Periodic Table

Period

Group or family

PeriodGroup or Family

Properties of MetalsProperties of Metals Metals are good conductors of heat and electricity

Metals are malleable

Metals are ductile

Metals have high tensile strength

Metals have luster

Examples of MetalsExamples of Metals

Potassium, K reacts with water and must be stored in kerosene

Zinc, Zn, is more stable than potassium

Copper, Cu, is a relatively soft metal, and a very good electrical conductor.

Mercury, Hg, is the only metal that exists as a liquid at room temperature

PropertiesProperties of Nonmetalsof Nonmetals

Carbon, the graphite in “pencil lead” is a great example of a nonmetallic element. Nonmetals are poor conductors of heat and electricity

Nonmetals tend to be brittle Many nonmetals are gases at room temperature

Examples of NonmetalsExamples of Nonmetals

Sulfur, S, was once known as “brimstone”

Microspheres of phosphorus, P, a reactive nonmetal

Graphite is not the only pure form of carbon, C. Diamond is also carbon; the color comes from impurities caught within the crystal structure

Properties of MetalloidsProperties of Metalloids

Metalloids straddle the border between metals and nonmetals on the periodic table.

They have properties of both metals and nonmetals. Metalloids are more brittle than metals, less brittle than most nonmetallic solids Metalloids are semiconductors of electricity Some metalloids possess metallic luster

Silicon, Si – A MetalloidSilicon, Si – A Metalloid

Silicon has metallic luster Silicon is brittle like a nonmetal Silicon is a semiconductor of electricity

Other metalloids include:

Boron, B Germanium, Ge Arsenic, As Antimony, Sb Tellurium, Te

  Easily lose valence electron (Reducing agents) +1

 Soft enough to cut with a knife

React violently with water  Stored in Oil React with halogens to

form salts

The Properties of a Group: The Properties of a Group:

the Alkali Metalsthe Alkali Metals

The Properties of a Group The Properties of a Group IIA: IIA: Alkaline Earth Metals Alkaline Earth Metals

2 e- in outer shell Will lose 2 e- : +2  

Group IIIA: The Boron Group IIIA: The Boron FamilyFamily

3 e- in the outer shell

B- metalloid, All other elements are metals, will form then 3+ ions

Al- 3rd most abundant element in earth’s crust, very strong in alloys, doesn’t corrode easily

Group IVA: Group IVA: Carbon FamilyCarbon Family

4 e- in outer shell

Si: 2nd most abundant in Earth’s crustSiO2 is in sand, semi conductor, silica=glass

Ge: electronic devices   Sn: coats steel for “tin cans”  Pb: In batteries and computer, used to be in paint and gas

Group VA: Group VA: Nitrogen Family Nitrogen Family

5 e- in outer shell N & P: NonmetalsAs & Sb are metalloidsBi: Metal

N: 79% of earth’s atmosphere, colorless, odorless and diatomic (N2 )

P: in your bones; in fertilizers, detergents, soft drinks

Group VIA: Group VIA: Oxygen FamilyOxygen Family

6 e- in outer (normally will gain 2e-; 2- charge then)

O, S, Se: NonmetalsTe: metalloidPo: metal (metalloid)

O: most abundant element on earth, colorless, odorless, diatomic (O2); extremely reactive, O3

S: unpleasant odor; added to natural gas to detect leaks; skunks, rotten eggs

The Properties of The Properties of Group VIIA: Group VIIA: The Halogens The Halogens

Contain 7 e- in outer shell

Easily gain valence electron (Oxidizing agents) -1   Can be prepared from their “salt” NaCl Cl2 NaF F2

 KBr Br2

Group VIIIA: Noble GasesInert Elements

Filled Outer Energy (filled s and p’s)8e- in outer shell; chemically inactive  

Half of the distance between nucli in covalently bonded diatomic molecule

"covalent atomic radii"

Periodic Trends in Atomic Radius

  Radius decreases across a period Increased effective nuclear charge due to decreased shielding

  Radius increases down a group Addition of principal quantum levels

Determination of Atomic Radius:Determination of Atomic Radius:

Table of Table of Atomic Atomic

RadiiRadii

  Increases for successive electrons taken from the same atom

  Tends to increase across a period

Electrons in the same quantum level do not shield as effectively as electrons in inner levels

    Irregularities at half filled and filled sublevels due to extra repulsion of electrons paired in orbitals, making them easier to remove

  Tends to decrease down a groupOuter electrons are farther from the nucleus

Ionization EnergyIonization Energy - the energy required to - the energy required to remove an electron from an atomremove an electron from an atom

Table of 1Table of 1stst Ionization Energies Ionization Energies

Ionization of MagnesiumIonization of Magnesium Mg + 738 kJ Mg+ + e-

Mg+ + 1451 kJ Mg2+ + e-

Mg2+ + 7733 kJ Mg3+ + e-

Another Way to Look at Ionization EnergyAnother Way to Look at Ionization Energy

ElectronegativityElectronegativity

The ability of an The ability of an atom in a atom in a molecule to molecule to attract shared attract shared electrons to electrons to itself.itself.

Linus Pauling 1901 - 1994

Table of Electronegativities

ElectronegativityElectronegativity

A measure of the ability of an atom in a chemical compound to attract electrons

  Electronegativities tend to increase across a period

  Electronegativities tend to decrease down a group or remain the same

Periodic Table of ElectronegativitiesPeriodic Table of Electronegativities

Ionic RadiiIonic Radii

Cations

  Positively charged ions formed when an atom of a metal loses one or more electrons   Smaller than the corresponding atom

Anions

Negatively charged ions formed when nonmetallic atoms gain one or more electrons Larger than the corresponding atom

Table Table of Ion of Ion SizesSizes

Summation of Periodic TrendsSummation of Periodic Trends