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