An ELECTRON DOT DIAGRAM is a model of an

atom in which each dot represents a valence electron.

Draw dot diagrams for H, He, Be, and Br!

Elements are stable when the highest occupied energy level is

filled with electrons.

• How many electrons would sulfur, S, like in order to obtain a stable configuration?

• How about Mg?

• Sometimes like elements may combine to form a stable electron configurations.

• Example: H, O, F, Br, N, Cl becomes….

H2, O2, F2, Br2, N2, Cl2,

• In these instances, the elements share valence electrons. This is an example of a covalent bond.

An element in Group 7A would be most likely to combine with

an element from which Group?

An element in Group 7A would be most likely to combine with

an element from Group 1A because Group 7A elements

need one electron to be stable while elements in Group 1A readily donate one electron.

An element in Group 5A would be most likely to combine with

an element from which Group?

An element in Group 5A would be most likely to combine with an element from Group 3A.

An element in Group 6A would be most likely to combine with

two elements from which Group?

An element in Group 6A would be most likely to combine with two elements from Group 1A.

Example: Li2O In this example, two lithium

atoms are represented with the

subscript 2.

Ionic Bonds

• Ionic bonds occur when electrons are transferred from one atom to another.

• This is most likely to occur when a metal and a non-metal bond!

Covalent Bonds

• Covalent bonds occur when electrons are shared between atoms.

• This is most likely to occur during transition metal to non-metal bonds, or when di-atomic elements bond such as the H O F Br N Cl’s.

Ionization Energy

• Is the amount of energy required to remove one of the valence electrons from an element.