1. Chemical Bonds
All atoms seek a state of balance - a full outer shell of electrons
Number of electrons in the outer orbit (shell) gives the element its chemical & physical properties
All atoms want to have an electron structure of a noble (inert) gas

2. Chemical Bonds Therefore: a chemical bond is produced
Atoms bond together to form a compound
Compound - a combination of elements
Compounds can be a solid, liquid, or a gas

3. Chemical Bonds Molecule Result of a chemical bond
Smallest particle with its unique identity
Water - H2O
Air – O2
N - 78%
O - 21%
Ar - 1%

4. Chemical Bonds Valence electrons Chemical Bonds
Electrons located in the outer orbit (shell)
Participate in chemical bonding
Inner orbits are stable
Chemical Bonds
A process of transfer, (giving/receiving) or sharing of electrons in order to reach a stable state
3 types
Ionic bonds
Covalent bonds
Metallic bonds

5. Chemical Bonds Ionic bond
Electrons are transferred (received or given-up)
+ or - ion is formed
Metal from the left side of the PT reacts with a nonmetal from the right side of the PT Sodium
Chloride - NaCl - table salt
Sodium - left - 1 electron to give
Chlorine - right - needs 1 electron

6. Chemical Bonds Covalent Bonds Electrons are shared
Nothing given or received
Form between the nonmetallic elements (right)

7. Chemical Bonds Examples of Covalent bonds Hydrogen Chloride Methane
HCl
Hydrogen Chloride
CH4
Methane
H2O
Water
SiO2
Quartz
CCl4
Carbon tetrachloride CO
Carbon monoxide
C6H12O6
Glucose

8. Chemical Bonds
Metallic bonds
Electrons are shared

9. Chemical Bonds Ionic Bond vs Covalent Bond Ionic bonds Covalent bond
Electrons are transferred
Form between metals & nonmetals
Metals – left side of PT
Nonmetals – right side of PT
Covalent bond
Electrons are shared
Forms between nonmetals

10. Chemical Bonds Electronegativity An atom’s pulling ability
Difference in the electronegativity will determine the bond type
Fig (p. 259)

11. Chemical Bonds Compound Names
ide suffix - compound contains 2 elements