Chemical Compounds – Ionic Compounds

Ionic Bond = forces of attraction that bind oppositely charged ions

- give/take or transfer of electrons!

- Recall:

Cations = positively charged atoms that have lost electrons.

Anions = negatively charged atoms that have gained electrons.

- Oppositely charged atoms attract each other.

Ex: NaCl

Na

Cl

1 valence electron

give 1 electron away to become stable!

7 valence electrons

take 1 electron away to become stable!

Na⁺¹

Cl^-1

Cation

Gave away 1 electron

Anion

Gained 1 electron

+

−

Attraction!

The attraction between positive and negative charges is the IONIC BOND!

Ionic Compounds = a neutral compound composed of positive and negative ions.

★ Total number of + and − charges MUST be equal!!! ★

Ex: Na + Cl =

Ex: Al + Br =

NaCl

AlBr₃

Properties of Ionic Compounds

1) At room temperature most ionic compounds are crystalline solids.

- component ions are arranged in repeating 3-D patterns.

The beauty of crystalline solids, such as these, comes from the orderly arrangement of their component ions.

​

Properties of Ionic Compounds

1) At room temperature most ionic compounds are crystalline solids.

- component ions are arranged in repeating 3-D patterns.

2) Very stable structure = high melting points!

3) When melted or dissolved ionic compounds can conduct an electric current (MUST HAVE MOBILE CHARGES!!!)