Chemical Bonding: Attractive forces that holds two or more atoms or ions together in a molecule or ion.
Objections against Octet Rule
Expanded Octet
PCl₅
PCl₆
Incomplete Octet
Odd electron molecules
H₂SO₄
SO₂
BeF₂
NO₂
ClO₂
NO
BeCl₂
BCl₃
AlCl₃
SCl₄
SF₆
ClF₃
IF₇
Valence Bond Theory: Proposed by Heitler, London. Developed by Pauling, Slater.
Formed due to overlapping of half filled valence shell orbitals.
Density of shared electron pair is concentrated ,ostly on internuclear axis
Strength of bond ∝ Extent of overlap
Along INA leads to σ bond
Perpendicular to INA lead to π bond
Strong
Weak
Types of Bonds
Ionic: Formed by transfer of electrons between low IP atom and high EA atom
Covalent:
Cations
Fe2+
Fe3+
Co3+
Ni2+
Cu2+
Metallic