3.VSEPR and hybridisation (1)

VSEPR Theory

A model used in chemistry to predict the shape of molecules based on the arrangement of electron pairs around a central atom.

Lone Pair

A pair of non-bonding electrons that occupies more space around a central atom than bonding pairs.

Bond Angle

The angle between two adjacent bonds formed by a central atom in a molecule.

Hybridization

The mixing of atomic orbitals to form new, equivalent hybrid orbitals for bonding in molecules.

sp³ Hybridization

Involves mixing one s orbital and three p orbitals, resulting in four equivalent sp³ hybrid orbitals arranged in a tetrahedral shape.

Trigonal Planar Shape

A molecular geometry with three bonded pairs and a bond angle of 120°.

Octahedral Shape

A molecular geometry with six bonded pairs and a bond angle of 90°.

Sigma Bond (σ)

A covalent bond formed by the direct overlap of orbitals, allowing for electron sharing between two atoms.

Pi Bond (π)

A covalent bond formed by the side-to-side overlap of unhybridized p orbitals, resulting in a bond above and below the molecular plane.

Trigonal Pyramidal Shape

A molecular geometry with three bonded pairs and one lone pair, resulting in bond angles slightly less than 109.5°.