1. Mg2+ (g), O2- (g) less stable  Mg2+ (g), O- (g) Mg+ (g), O (g)
Chapter 5 Periodic Trends Chapter 7 Chemical Formulas and Bonding Date ___________
Just why do Mg atoms lose 2e- ?
Just why do O atoms gain 2e- ?
Mg2+ (g), O2- (g)
less stable 
Mg2+ (g), O- (g)
Mg+ (g), O (g)
Mg+ (g), O- (g)
Mg+O- (s)
Mg (g), O (g)
 more stable
Mg (s), ½ O2 (g)
Mg2+O2- (s)

2. so,… it’s not that ions with FOS (“noble ions”) are inherently stable
like their stable noble atoms “pals”
in fact, these “noble ions” are unstable
… but, the compounds that form from these “noble ions” ARE particularly stable
any ions that form that do not have FOS,
lead to compounds that are LESS stable
than the compounds that form from their “noble ion” pals
AND
than their parent neutral atoms

3. Mg2+ and O2- have FOS
BUT,
they are not more stable
than their parent atoms
Mg2+ (g), O2- (g)
less stable 
2nd EAE O
Mg2+ (g), O- (g)
the “noble ions” form,
NOT because they
are stable
BUT because…
2nd IE Mg
1st EAE O
Mg+ (g), O (g)
Mg+ (g), O- (g)
1st IE Mg
formation of ionic bond…
… energy is released
isolated
atoms
Mg+O- (s)
Mg (g), O (g)
Mg+O- is LESS stable
than the pure elements
 more stable
Mg (s), ½ O2 (g)
Mg2+O2- is MORE stable
than the pure elements
Mg2+O2- (s)

4. Mg2+ (g), O2- (g)
less stable 
so,… it’s not that ions with FOS (“noble ions”) are inherently stable
like their stable noble atoms “pals”
in fact, these “noble ions” are unstable
… but, the compounds that form from these “noble ions” ARE particularly stable
any ions that form that do not have FOS,
lead to compounds that are LESS stable
than the compounds that form from their “noble ion” pals
AND
than their parent neutral atoms
Mg2+ (g), O- (g)
Mg+ (g), O (g)
Mg+ (g), O- (g)
Mg+O- (s)
Mg (g), O (g)
Mg+O- is LESS stable
than the pure elements
 more stable
Mg (s), ½ O2 (g)
Mg2+O2- is MORE stable
than the pure elements
Mg2+O2- (s)

5. they are not more stable than their parent atoms Mg2+ (g), O2- (g)
Chapter 5 Periodic Trends
Just why do Mg atoms lose 2e- ?
Just why do O atoms gain 2e- ?
Mg2+ and O2- have FOS
BUT
they are not more stable
than their parent atoms
Mg2+ (g), O2- (g)
less stable 
2nd EAE O
Mg2+ (g), O- (g)
2nd IE Mg
1st EAE O
Mg+ (g), O (g)
Mg+ (g), O- (g)
1st IE Mg
isolated
atoms
Mg+O- (s)
Mg (g), O (g)
 more stable
Mg (s), ½ O2 (g)
Mg2+O2- (s)