Covalent Bonding
Why do atoms bond?
To fill their 8 valence electrons requirement to achieve stability.
What is a covalent bond & how is it different from an ionic bond?
Covalent bonds occur to share electrons between atoms so the atoms bond as one.
Ionic bonds move electrons, but atoms stay apart.
What types of atoms are involved in a covalent bond?
Only non-metal atoms.
Why do atoms bond?
Atoms are able to achieve their octet by sharing electrons.
Shared electrons are considered part of the complete outer energy level for both atoms in the bond.
Molecule
Formed when 2 or more atoms bond covalently.
Example: proteins, carbohydrates, DNA, synthetic fibers (wool, cotton).
Diatomic Molecule
2 atoms that can fill their octet by bonding with another atom of the same element.
Seven of these: H, N, O, F, Cl, Br, I.
Single Covalent Bonds (Sigma Bonds)
Only occur when one pair of electrons is shared.
Group 7A wants one electron: one covalent bond.
Group 6A wants two electrons: two covalent bonds.
Multiple Covalent Bonds
When two atoms share more than one pair of valence electrons.
Double bond = 4 electrons total.
Triple bond = 6 electrons total.
The elements carbon, nitrogen, oxygen, and sulfur often form multiple bonds.
Naming Covalent Compounds
General Rules
The first element is named first and in full.
The second element is named using root and the suffix "-ide".
Prefixes are used to indicate how many of what is in the compound.
Exception: No use of "mono" if there’s only one of the first element.
Prefixes
1: Mono
2: Di
3: Tri
4: Tetra
5: Penta
6: Hexa
7: Hepta
8: Octa
9: Nona
10: Deca