3.1: The Periodic Table

Define Valance Electrons

the number of electrons in the highest occupied energy level for an element

Distinguish between the term group and period

Groups are vertical arrangements of elements in the periodic table that have the same number of valance electrons, were as Periods are horizontal arrangements of elements in the periodic table that have equal numbers of energy levels

Define Periods

The members across (horizontally) the table. They have equal numbers of energy levels.

What are the energy levels

2,8,18,32

Define Groups

A group is the vertical arrangement of elements in the periodic table. There are eight groups. The members of the same group have the same amount of valence electrons.

How to determined the group number of an element

Determined by the group number by the number of valence electron in the last energy level (the first energy level have two electrons, the second eight, the third also eight or eighteen). For example If the atom has no valance electron then it is a noble gas

Apply the relationship between the number of electrons in the highest occupied energy level for an element and its position in the periodic table.

If you are able to determine how many valence electrons there are in the outermost shell you can determine which group and which period an element exist in.

Define atomic number

The amount of protons in the nucleus of an atom

Apply the relationship between the electron arrangement of elements and their position in the periodic table

The electron arrangement of elements determine were the atom is on the periodic table vertically (number of valance electrons) and horizontally (Energy level)

Describe the arrangement of elements in the periodic table in order of increasing atomic number

The way the periodic table is arranged is that the elements that have equal amounts of valence electrons in their outermost shell are placed in order of increasing atomic numbers vertically.

Describe the arrangement of elements in the periodic table in horizontal order (period)

how many shells (energy level) the elements in the same horizontal row have