Ionic and Covalent Compounds

How many valence electrons do atoms need in the highest energy

level to be stable?

8

How do atoms achieve stability?

By gaining or losing electrons

Why are valence electrons important?

Valence electrons are the electrons

involved in bonding

Covalent Compounds

• Bond between non-metals

• Neutral atoms share electrons

• When a compound is formed by sharing electrons, it is called a molecule

What is the result of this bond?

Which of the following are molecules?

H2O

CO2

NaCl

Mg3P2

N2O5

Ionic Compounds

• Bonds between metals + non-metals

• One atom gains an electron, one atom loses an electron

• Electrons are transferred

Which are Ionic Compounds?

Charges on an atom

Why does the red atom lose an electron?

Why does the blue atom gain an electron?

What happens to the charge of the red atom?

What happens to the charge of the blue atom?

To achieve 8 electrons on outer orbital

To achieve 8 electrons on outer orbital

It loses an electron (-), so it becomes positive

It gains an electron (-), so it becomes negative

Ionic Vs. Covalent Compounds

Complete a Venn Diagram using the following terms:

1. Transferred electrons2. Shared electrons3. Bond to achieve full

outer orbital4. Metal + Non-metal5. Only non-metals

ionic covalent

11 2

34

5

Properties of Ionic and Covalent Compounds

Ionic Compounds• High melting points• High boiling points• Conduct electricity

when dissolved in water

Covalent Compounds• Low melting points• Low boiling points• Do not conduct

electricity