The Periodic Table8.5C: Interpret the arrangement of the Periodic Table, including groups and periods to explain how properties are used to classify elements.

How are elements arranged on the Periodic Table of Elements?

Elements are arranged by increasing atomic number (number of protons).

When elements are arranged by increasing atomic number, there is a tendency for the properties of the elements to repeat in a periodic pattern. The word periodic means “occurring or

appearing at regular intervals.”

How does the atomic mass change as you move through the Periodic Table?

In general the atomic mass increases as you move from left to right on the Periodic Table.

Reminder: Atomic mass is equal to the number of protons and neutrons in an atom.

What are the rows and periods on the Periodic Table called?

Columns (up and down) are called groups or families. Rows (side to

side) are called periods.

What does location on the Periodic Table tell us about an element?

We can use an element’s location on the Periodic Table to determine its physical and chemical properties.

What are the three main sections of the Periodic Table?

Metals  Metalloids  

   

Nonmetals          

             

                                   

                                   

                                   

         

Properties of metals, nonmetals, metalloids Metals – Left of the zigzag line, good

conductors, poor insulators, malleable, ductile, high luster

Nonmetals – Right of the zigzag line, poor conductors, good insulators, brittle, low luster

Metalloids – touching the zigzag line, properties of both metals and nonmetals

How are elements in the same period related? Elements in the same period have the

same number of energy levels. They have just about nothing else in common

Lithium, Carbon, and Neon are all in Period 2 and they all have 2 energy levels.

How are elements in the same group related? Groups are sometimes called “Families”

because all of the elements in a group have similar properties.

Elements in the same group have the same number of valence electrons.

Reminder – Valence electrons determine an elements chemical reactivity. So, elements in the same group have similar reactivity levels.

Look at your periodic table

Which element is most similar to Nitrogen? • Phosphorus • Carbon and Oxygen may be more similar in mass but it

looks and acts like phosphorus – they are in the same FAMILY!!!

What are the properties of Group 1, the Alkali Metals?

The elements in Group 1 have 1 valence electron. These elements are highly reactive because they

have one valence electron. These elements are metals and are malleable,

ductile and good conductors of heat and electricity.

Hydrogen shares some properties with this group, but it is actually a nonmetal.

What are the properties of Group 2, the Alkaline Earth Metals?

The elements in Group 2 have 2 valence electron.

These elements are highly reactive because they have two valence electron.

These elements are metals and are malleable, ductile and good conductors of heat and electricity.

What are the properties of Transition Metals?

These elements have a variable amount of valence electrons (we won’t worry about that this year)

These elements are metals and are ductile, malleable, and good conductors.

What are the properties of Groups 13 – 16?

These Groups have a combination of metals, nonmetals and metalloids.

Group 13- 3 valence electrons

Group 14- 4 valence electrons

Group 15- 5 valence electrons

Group 16- 6 valence electrons

What are the properties of Group 17, the Halogens?

These elements have 7 valence electrons. These elements are all highly reactive

because they have 7 valence electrons. These elements are dull, brittle, poor

conductors and liquid or gas at room temperature.

What are the properties of Group 18, the Noble Gases? These elements have 8 valence

electrons (2 for helium) These elements have a complete outer

energy level so they do not react.

What are the properties of the Rare Earth Elements?

This group is composed of the Lanthanide and the Actinide series.

Most of the actinides are man made. These elements belong in Group 3

and the 6th and 7th periods.