The Periodic Table

History of the Periodic Table

Dmitri Mendeleev organized

elements according to their

increasing atomic mass and their

physical properties

Lother Moseley arranged the

periodic table according to the

atomic number

Dmitri Mendeleev’s Table

Reading the Squares

Each square on the periodic table

represents one atom

In each square it tells the following

information about each element

Atomic Number

Atomic Mass

Element Name

Element Symbol

Reading the Periodic Table

Each horizontal row of elements (from

left to right) is called a period

Elements follow a repeating pattern

as you move across the period

Each period moves from metals to

nonmetals

Horizontal row is the

period

Reading the Periodic Table

Each column of elements (top to

bottom) are called a group

Elements in the same group have

similar physical and chemical

properties

Sometimes groups are called

families

Vertical column is the

group

Properties

Determined by the number of

electrons in the outer energy

level of the atom

Same number in the outer shell

will be in same group

oxygen

K Na

lithium potassium

Corrode

sodium

oxygen

Reading the Periodic Table

Elements are classified as metals,

nonmetals and metalloids

The zigzag line on the periodic table

helps you to recognize which

elements are metals, nonmetals and

metalloids

The color of the element symbol tells

whether it is a solid, liquid or gas

Color your table as metals,

metalloids, and non-metals.

Metals

Metals are to the LEFT of the

zigzag line

Most elements are metal

Most metals are solid at

room temperature Exception to the rule: Hg (mercury)

is liquid at room temperature

Metals

Three or fewer electrons in the

outer shell

Good conductor of heat and

electricity

Shiny luster

Malleable

Nonmetals

Nonmetals are to the RIGHT

of the zigzag line

Found as a solid and a gas Exception: (Br) Bromine only liquid

non metal.

Nonmetals

Five or more electrons in the

outer shell

Lack luster

Does not conduct heat or

electricity

Not malleable

Metalloids

Elements that border the

zigzag line

Metalloids have some

properties of metals and

some properties of

nonmetals

Metalloid

Has properties of

both

Found along the

zigzag line

Example:

(Te)Tellurium