1. Electron Arrangements

2. Electron Arrangements
Energy Level (also called orbit, shell, or orbital):
where an electron can be found, at a specific
distance outside the nucleus

3. Electron Arrangements
Bohr-Rutherford Diagram:
Fluorine 19 F 9

4. Electron Arrangements
...but we're mostly interested in the outermost shell

5. Electron Arrangements
...but we're mostly interested in the outermost shell
Valence shell: the outermost energy level,
responsible for how the atom bonds with
other atoms

6. Electron Arrangements
...but we're mostly interested in the outermost shell
Valence shell: the outermost energy level,
responsible for how the atom bonds with
other atoms
Family (also called group): indicates the number
of electrons in the valence shell
e.g. Family IIIA has 3 valence electrons

7. Electron Arrangements
Lewis Structure: a method of representing the
arrangement of valence electrons of an element
e.g.

8. Electron Arrangements
Lewis Structure: a method of representing the arrangement of valence electrons of an element
e.g.
Stable Octet: a completely filled valence shell
-usually 8 e- 's, but 2 in the case of H & He

9. Electron Arrangements
How do atoms gain a stable octet?

10. Electron Arrangements
How do atoms gain a stable octet?
Ionic bonding: the metal gives away electrons to the non-metal
-metal's valence shell is now the one below
which is already full

12. Electron Arrangements
How do atoms gain a stable octet?
Covalent bonding: electrons are shared between atoms so they feel full

13. Electron Arrangements
How do atoms gain a stable octet?
Covalent bonding: electrons are shared between atoms so they feel full
e.g. hydrogen + sulfur dihydrogen monosulfide

14. Electron Arrangements
How do atoms gain a stable octet?
Covalent bonding: electrons are shared between atoms so they feel full
e.g. hydrogen + sulfur dihydrogen monosulfide
bonding pair: electrons shared between atoms
lone pair: electrons forming unshared pairs

15. Electron Arrangements
Identify the:
i. bonding pairs ii. lone pairs

16. Electron Arrangements
Identify the:
i. bonding pairs ii. lone pairs

17. Electron Arrangements
How do atoms gain a stable octet?
Covalent bonding: electrons are shared between atoms so they feel full
double bonds
e.g. carbon + sulfur carbon disulfide

18. Electron Arrangements
Identify the:
i. bonding pairs ii. lone pairs

19. Electron Arrangements
Identify the:
i. bonding pairs ii. lone pairs