This document discusses ion formation and naming ions. It explains that atoms become ions by gaining or losing electrons to obtain a full outer electron shell of 8 electrons. It gives examples of common monatomic cations such as K+, Ca2+, and Al3+ and anions such as S2-, O2-, Br-, and N3-. The document also provides guidelines for naming ions, indicating that positive ions are called cations and named after the element, while negative ions are called anions and named by taking the element root and adding -ide.

1. 5.1

2. Ions
• When atoms are in their pure form,
they are neutral.
• Neutral atoms can become charged by:
– losing electrons
– gaining electrons
• When they do this they become IONS.

3. • Atoms become ions by obeying
the octet rule.
– All atoms want a full outer shell.
– A full outer shell = 8 electrons
Octet Rule

4. The elements are
arranged in groups

5. All elements want 8 e- in the
valence shell to be stable.
Group
#
# of
valence
electrons
electrons
lost or
gained
Ion
Charge

6. Ion Formation

7. Ionic Charge

8. Ion Formation

9. Ionic charge

10. Naming Ions
• Positive ions are
Cations
• Use the name of
the element.
• Negative ions are
Anions
• Use the root of
the element, drop
ending and add –
”ide”.K+1
Ca+2
Al+3
Potassium ion
Calcium ion
Aluminum ion
S-2
O-2
Br-1
N-3
Sulfide ion
Oxide ion
Bromide ion
Nitride ion

11. Homework
• READ: pages 158-165
–Be sure you understand the
connection between orbitals
and valence electrons!
• Do: p.165 1-13