Gilbert Newton Lewis

(surrounded by pairs of

electrons)

Lewis Dot Structures &

Covalent Bonding

Lewis-Dot Structures• Find out which group

(column) your element is in.

• This will tell you the number of valence electrons your element has.

• You will only draw the valence electrons.

Groups - Review

•Each element in a group has the same number of electrons in their outer orbital, also known as “shells”.

Except for He, it has 2 electrons

•The electrons in the outer shell are called “valence electrons”

Lewis-Dot Structures

1) Write the element symbol.

2) Carbon is in the 4th group, so it has 4 valence electrons.

3) Starting at the right, draw 4 electrons, or dots, counter-clockwise around the element symbol.

Lewis-Dot Structures

Try these elements on your own:

a) Hb)Pc) Cad)Ar

Lewis-Dot Structures

Try these elements on your own:

a) Hb)Pc) Cad)Ar

Lewis-Dot Structures

Try these elements on your own:

a) Hb)Pc) Cad)Ar

Lewis-Dot Structures

Try these elements on your own:

a) Hb)Pc) Cad)Ar

Lewis-Dot Structures

Symbols of atoms with dots to represent the valence-shell electrons

1 2 13 14 15 16 17 18H He:

Li Be B C N : O : F :Ne :

Na Mg Al Si P : S :Cl :Ar :

In an IONIC bond,electrons are lost or gained,resulting in the formation of IONSin ionic compounds.

FK

FK

FK

FK

FK+ _

FK+ _

The compound potassium fluorideconsists of potassium (K+) ions

and fluoride (F-) ions

FK+ _

The ionic bond is the attractionbetween the positive K+ ion

and the negative F- ion

In covalent bonding,atoms still want to be likea noble gas (the octet rule).

But rather than losing or gaining electrons, atoms now share an electron pair.

Covalent bonding example:

Carbon =

Covalent bonding example:

Carbon now has an octet.

All hydrogen atoms now have 2 electrons