Molecular Geometry and Hybridization

Flashcards covering key terms and definitions related to molecular geometry, VSEPR theory, hybridization (sp3, sp2, sp), Lewis structures, line-angle formulas, ball-and-stick models, and valence bond theory from the lecture.

VSEPR Theory

States that electrons are most stable when they're as far away as possible from other electrons.

Electron Domain

Regions around a central atom where electrons are located, including bonding pairs and lone pairs.

Tetrahedral Geometry

An electron domain geometry with four electron domains, resulting in approximate bond angles of 109.5 degrees.

Trigonal Planar Geometry

An electron domain geometry with three electron domains, resulting in approximate bond angles of 120 degrees.

Linear Geometry

An electron domain geometry with two electron domains, resulting in approximate bond angles of 180 degrees.

Wedge and Dash Notation

A drawing technique used to represent molecules in three dimensions, showing bonds coming out towards the viewer (wedge) or going away (dash).

Line-Angle Formulas (Line Structures)

A structural shorthand for organic chemists where carbon atoms are implied at the end and vertex of every line, heteroatoms are shown explicitly, and hydrogens bonded to carbon are implicit.

Heteroatoms

Any atom that is not carbon or hydrogen within an organic molecule.

Valence Bond Theory (VBT)

Describes covalent bonds as forming from the overlap of two half-filled orbitals, leading to increased electron density between atoms.

Hybridized Orbital Theory (HO Theory)

An orbital mixing model that explains aspects of bonding not explained by pure atomic orbitals, where atomic orbitals mix to create hybrid orbitals that are a weighted average.

Hybrid orbitals

Orbitals formed by the mixing of atomic orbitals, which then overlap with other orbitals to form bonds.

sp3 Hybridized Orbitals

Hybrid orbitals formed from one s and three p atomic orbitals, a tetrahedral geometry.

Sigma (σ) Bonds

Covalent bonds that result from the direct, head-on overlap of orbitals along the bonding axis; all single bonds are sigma bonds.

sp2 Hybridized Orbitals

Hybrid orbitals formed from one s and two p atomic orbitals, orbitals arranged in a trigonal planar geometry.

Carbocations

Highly reactive organic intermediates that are sp2 hybridized, possessing an empty p orbital.

Pi (π) Bonds

Covalent bonds that result from the sideways overlap of adjacent, parallel p orbitals, found in double and triple bonds.

Coplanar Atoms

Atoms within a molecule that lie within the same plane.

sp Hybridization

Hybridization that occurs on bonded atoms with two electron domains, a linear geometry approximately 180 degrees apart, and two unhybridized p orbitals for pi bonds.