The Periodic LawThe Periodic Law

Mendeleev’s Periodic Table (1872)Mendeleev’s Periodic Table (1872)

Dmitri Mendeleev1st to publish an organized table of elements.

Grouped elements by similar chemical properties. Arranged elements by increasing mass.

Henry Moseley (1913)Henry Moseley (1913)

Grouped elements by similar chemical properties.

Arranged elements by increasing atomic number.

Used X-Ray diffraction to determine how many protons are in an atom of an element.

Modern Russian TableModern Russian Table

Chinese Periodic TableChinese Periodic Table

Stowe Periodic TableStowe Periodic Table

A Spiral Periodic TableA Spiral Periodic Table

““Mayan” Mayan” Periodic Periodic

TableTable

Orbital filling tableOrbital filling table

The Periodic TableThe Periodic Table

Period

Group or family

PeriodGroup or Family

Properties of MetalloidsProperties of Metalloids

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

Nonmetals

Metals

Metalloids

Periodic Table with Group NamesPeriodic Table with Group Names

Inner Transition Metals

Transition

Metals

Alk

ali M

eta

ls

Alk

alin

e E

art

h M

eta

ls

Halo

gen

s

Nob

le G

ases

Boro

n F

am

ily

Carb

on

Fam

ily

Nit

rog

en

Fam

ily

Oxyg

en

Fam

ily

PeriodGroup or Family

Easily lose valence electron (Reducing agents)

React violently with water Large hydration energy React with halogens to

form salts

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

the Alkali Metalsthe Alkali Metals

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 an example of a nonmetallic element.

Nonmetals are generally poor conductors of heat and electricity Nonmetals tend to be brittle Unlike carbon, (a solid), many nonmetals tend to be 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

Nonmetals

Metals

Metalloids

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

Periodic means Periodic means Repeating PatternRepeating Pattern. . Do you see a repeating pattern for these 1Do you see a repeating pattern for these 1stst Ionization Ionization

Energies?Energies?

11stst, 2, 2ndnd , and 3 , and 3rdrd, Ionization energies of Magnesium, Ionization energies of Magnesium Mg + 738 kJ Mg+ + e-

Mg+ + 1451 kJ Mg2+ + e-

Mg2+ + 7733 kJ Mg3+ + e-