Chemical Families& Lewis Dot Diagrams

Day 1 & 2

Intro to the Periodic table and valence electrons

There are 3 main classes of elements: metals, nonmetals, metalloids.

The Periodic Table

Outline the 3 groups on your Periodic Table: metals, nonmetals, metalloids.

The Periodic Table

Metals, Nonmetals, & Metalloids

Divide a piece of paper as shown Take notes on the following slides

metals nonmetalsLocated on left side of periodic table

Located on right side of periodic table

metals nonmetals

Solids at room temp. (except mercury)

Most are gases (some brittle solids)

Metals nonmetals

higher melting points lower melting points

metals nonmetals

malleable (can be pounded & shaped)

harder

brittle (break easily)

Softer than metals

metals nonmetals

Ductile (can be drawn into wire)

Not ductile

metals nonmetalslustrous (shiny)

metallic luster mostly silver or grayish white

dull

metals nonmetals

Good conductors of heat and electricity

Poor conductors (good insulators)

Metals nonmetals

Tend to lose electrons form positive ions +

Tend to gain electrons form negative ions -

Metals nonmetals

Form ionic compounds with nonmetals

Ionic bonds = transfer of electrons

Form covalent compounds with other nonmetals

Covalent bonds = sharing of electrons

MetalloidsHave some properties of both metals & nonmetalsShiny, brittle solidsLimited conductivityLocated along stair step line in between metals & nonmetalsUses: semiconductors (Used in electronics), glass, alloys

Vertical columnsHorizontal rowscalled groups or families.

Elements in a group have similar chemical & physical properties.

Numbered from 1-18 from left to right

called periods.

Elements within a period have properties that change progressively across the table.

The Periodic Table

The group A elements are called the representative elements.

1A 8A

2A 2A 3A 4A 5A 6A 7A

The Periodic Table

The group B elements are called the transition elements.The group B elements at the bottom are called the inner transition elements.

Transition

InnerTransition

The Periodic Table

The Periodic Table

Group 1A Alkali metals 1 valence electron is lost easily, forms a cation (ions with a positive charge) with a 1+ charge.

The group has similar physical properties

Metallic appearance.

The Periodic Table

Group 2A Alkaline earth metals 2 valence electrons that can be readily lost, forms a cation with a 2+ charge.

The group has similar physical properties

Metallic appearance.

The Periodic Table

Group 7A Halogens (nonmetals) highly reactive with 7 valence electrons, forming an anion (a negatively charged ion) with a 1- charge

The Periodic Table

Group 8A noble gases have a complete octet (8) of valence electrons

they have little tendency to gain or lose electrons and are non-reactive.

The Periodic Table

Group B transition metals in the middle of the Periodic Table

Number of outer electrons varies, leading to a variety of charges for each element.

they share many of their chemical and physical properties

The Lanthanide series and the Actinide series, located at the bottom of the periodic table, are the inner transition metals (the rare earth metals).

NobleGas

Metalloids(on the stair-step line)Inner Transition Metals

(f – block elements)

Label the following families on your Periodic Table

The Periodic Table

The A group number = the number of valence electrons (except for He)

1A

2A 3A 4A 5A 6A 7A

8A

Valence electrons = the # of dots for Lewis Dot Diagrams

Valence Electrons – outer electrons

The electron structure of an atom determines many of its chemical & physical properties. For the group A elements, the group number equals the number of valence electrons. (Except for Helium = 2) •He• Fill in the element symbols and valence electrons on the blank Periodic table

Lewis Dot Diagrams

Day 3Using the Internet or a borrowed Chemistry class set of books research and create the assigned Periodic Families Poster

Students will complete the worksheet summarizing the information found on each poster.

Day 4

Day 5Complete the Stemscopes Periodic Table Activity

Day 6Make flash cards of the elements and polyatomic ions using either index cards, notebook paper or construction paper

Day 7Re-write the list by grouping all of the ones with similar charges together.

Study with a partner for your quiz tomorrow. (You may use a Periodic table on the quiz)