The Periodic Table

What is the periodic table?

A table that displays all of the known elements

How are elements arranged in the periodic table?

In groups & periods by increasing atomic number

Groups are…

The vertical columns in the periodic table

The group number represents…

The number of electrons in the outer shell

Periods are…

The horizontal rows in the periodic table

The period number represents…

The number of electron shells

Why do elements in the same group have similar chemical properties?

Because they have the same number of electrons in the outer shell

Why are elements in group 8 / 0 less reactive?

Because they do not need to gain or lose any electrons as they already have a full outer shell

This makes them very stable

Electronic configuration is…

The number of electrons in each electron shell

Electronic configuration of Na

2, 8, 1

Electronic configuration of Mg

2, 8, 2

Electronic configuration of Al

2, 8, 3

Electronic configuration of O

2, 6

Electronic configuration of Cl

2, 8, 7

Electronic configuration of Ar

2, 8, 8

Where are metals & non-metals positioned on the periodic table?

How can metals be identified without the periodic table?

Conductors of electricity

Form positive ions

Have basic oxides which react with acids to give water & a salt

How can non-metals be identified without the periodic table?

Not conductors of electricity (except graphite)

Form negative ions

Have acidic or neutral oxides