Unit 3: The Periodic Table

The Periodic Law:

The Periodic Law:When the elements are arranged by increasing atomic number,

The Periodic Law:When the elements are arranged by increasing atomic number, there is a periodic repetition of their chemical and physical properties.

Dmitri Mendeleev (1834-1907)

Dmitri Mendeleev (1834-1907)

Dmitri Mendeleev (1834-1907)∙ First to notice the element's periodic repetition of properties.

Dmitri Mendeleev (1834-1907)∙ First to notice the element's periodic repetition of properties.∙ Designed the first periodic table (in 1869)

Today's Modern Periodic Table

Today's Modern Periodic Table(see back inside cover of text)

Wall Poster:

See Handout,The Divided Periodic Table

Periods:Horizontal rows, numbered 1-7.

Families (or Groups):

Families (or Groups):Vertical columns, numbered 1-18

Families (or Groups):Vertical columns, numbered 1-18(also 1A - 8 A)

Family Names"

Family Names" 1" Alkali metals (not hydrogen)

"

Family Names" 1" Alkali metals" 2 " Alkaline earth metals"

Family Names" 1" Alkali metals" 2 " Alkaline earth metals" 3-12 " The transition metals"

Family Names" 1" Alkali metals" 2 " Alkaline earth metals" 3-12 " The transition metals" 13 " The Boron family"

Family Names" 1" Alkali metals" 2 " Alkaline earth metals" 3-12 " The transition metals" 13 " The Boron family" 14 " The Carbon family"

Family Names" 1" Alkali metals" 2 " Alkaline earth metals" 3-12 " The transition metals" 13 " The Boron family" 14 " The Carbon family" 15 " The Nitrogen family"

Family Names" 1" Alkali metals" 2 " Alkaline earth metals" 3-12 " The transition metals" 13 " The Boron family" 14 " The Carbon family" 15 " The Nitrogen family" 16 " The Oxygen family"

" 17 " The Halogens"

" 17 " The Halogens" 18 " The Noble Gases

Semimetals(semiconductors or metalloids):

Semimetals (or metalloids):Elements that have properties of both metals and nonmetals.

Metals:

Metals:Those elements that are a good conductors of heat or electricity and generally shiny;

Metals:Those elements that are a good conductors of heat or electricity and generally shiny; most are solid, ductile, and malleable.

Nonmetals:

Nonmetals:Those elements that are generally gasses or dull, brittle solids and are poor conductors of heat and electricity.

The Inner Transition Metals:

The Inner Transition Metals:

Elements 58-71are called the Lanthanide series

The Inner Transition Metals:

Elements 58-71are called the Lanthanide series

Elements 90-103 are called the Actinide series

The Periodic Table can be broken into s, p, d, and f blocks,

The Periodic Table can be broken into s, p, d, and f blocks, corresponding directly with the predictions made by quantum mechanics.

By knowing an element's location on the Periodic Table, its electron configuration can be easily determined.

Valence Electrons

Valence Electrons (p152)•Responsible for an atom's chemical properties.

Valence Electrons (p152)•Responsible for an atom's chemical properties.

•Are lost, gained, or shared to form chemical bonds.

•Only found in the outermost energy level of an atom... therefore,

•Only found in the outermost energy level of an atom... therefore, only belong to the outermost and sublevels.

•Only found in the outermost energy level of an atom... therefore, only belong to the outermost s and p sublevels.

•Only found in the outermost energy level of an atom... therefore, only belong to the outermost s and p sublevels.

Making the maximum number of valence electrons any atom can have...

•Only found in the outermost energy level of an atom... therefore, only belong to the outermost s and p sublevels.

Making the maximum number of valence electrons any atom can have... 8 !

The numbering 1A - 8A is used to indicate the number of valence electrons in those families.

The numbering 1A - 8A is used to indicate the number of valence electrons in those families.

Therefore the transition elements all have only 2 valence electrons!

Valence Shell:

Valence Shell: The region of space occupied by an atom's valence electrons.

The Octet Rule

The Octet RuleAtoms tend to lose, gain, or share electrons to obtain a

"stable octet."

The Octet RuleAtoms tend to lose, gain, or share electrons to obtain a

"stable octet."

(The configurationof a noble gas!)

Ionic Charge overview:

Ionic Charge overview:

Metals lose valence electrons to become positive ions ("cations").

Ionic Charge overview:

Metals lose valence electrons to become positive ions ("cations").

Nonmetals and semimetalsusually gain valence electrons to become negative ions ("anions")

Charge Trend:

" Family" " " " " " " " " " " " ChargeAlkali metals" " " " " " " " " "Alkaline earth metalsBoronCarbon (nonmetals)Nitrogen (nonmetals)Oxygen (nonmetals)HalogensNoble Gases

Diatomic Elements:

Diatomic Elements: Elements that are found in nature as pairs of atoms; two identical atoms bonded together.

The Super Seven: H2 , N2 , O2 , F2 , Cl2, Br2 , and I2

Periodic Properties (Section 5.3)

Periodic Properties (Section 5.3)

Atomic Radius: the distance from the center of an atom's nucleus to its outermost electron.

Periodic Properties (Section 5.3)

Atomic Radius: the distance from the center of an atom's nucleus to its outermost electron.

(See Figure 3.2, page 143)

Trend:

Trend:

Increases as you move down a family

Trend:

Increases as you move down a family Decreases as you move across a period

Ionic Radius (figure 3.9, see p151)

Ionic Radius:

Trend:

Trend:

Increases as electrons are added (anions)

Trend:

Increases as electrons are added (anions)

Decreases as electrons are lost (cations)

Ionization Energy: energy required

to remove the outermost electrons

from a gaseous atom.

Ionization Energy: energy required to remove the outermost electron from a *gaseous atom.

Ionization Energy: energy required

to remove the outermost electron

from a *gaseous atom.

*a single, isolated atom.

Ionization Energy: energy required to remove the outermost electron from a *gaseous atom.(Turns the atom into a positive ion.)

Ionization Energy: energy required to remove the outermost electron from a *gaseous atom.(Turns the atom into a positive ion.)

(See Page 146)

Trend:

Trend:

Increases as you move across a period.

Trend:

Increases as you move across a period.

Decreases as you move down a family .

(See figure 3.6, page 147)

(See figure 3.6, page 147)

It takes a great deal more energyto remove a core electron!!!

There will be a huge jump in ionizationenergy when removing these!

Electronegativity:

Electronegativity: ability of an atom to attract electrons in a chemical bond.

Electronegativity: ability of an atom to attract electrons in a chemical bond.

(See Figure 3.11, page 153)

Trend:

Trend:

Decreases as you move down a family .

Trend:

Decreases as you move down a family .Increases as you move across a period.

Shielding effect:

Shielding effect:The repulsive force exerted on valence electrons by core electrons.

Shielding effect:The repulsive force exerted on valence electrons by core electrons. -

- lowers ionization energy

Shielding effect:The repulsive force exerted on valence electrons by core electrons. -

- lowers ionization energy - lowers electronegativity

Shielding effect:The repulsive force exerted on valence electrons by core electrons. -

- lowers ionization energy - lowers electronegativity - increases atomic radius