IONIC BONDING
Transition elements
- Can form more than one stable ion
- Can be distinguished by color
o Copper (2+, 1+)
o Lead (4+,2+)
o Hydrogen (H-, H+)
Ionic character
- Electronegativity difference > 1.8 --- ionic
- Highest tendency of forming ionic compounds on periodic table --- elements on
bottom left and top right
COVALENT BONDING
Number of shared electrons increases, bond length decreases, bond strength increases.
- Electrostatic attraction stronger so shorter bond length
Covalent character
- Electronegativity difference < 1.8 --- covalent
- Position on periodic table of 2 elements closer, more covalent
Polarity
- Unsymmetrical bond --- polar
- Dipole --- the bond has an area of positive charge and an area of negative charge
(delta)
- Electronegativity differences
o 0.0 – 0.4 --- non-polar covalent
o 0.4 – 1.8 ---polar covalent
o Equal or > 1.8 --- ionic
Electronegativity = ability of an atom to attract shared electrons in covalent bond