Organic Chemistry - Orbitals and Bonding Vocabulary

Vocabulary flashcards covering atomic orbitals, molecular orbital theory, energy level diagrams, electronic principles, and sp3 hybridization.

Reactivity vs Stability

Polar opposites on an energy level diagram; higher potential energy corresponds to greater reactivity, whereas lower energy corresponds to greater stability.

Degenerate Orbitals

Orbitals within the same shell that possess the exact same energy level, such as the three p orbitals or five d orbitals.

s Orbital

A spherical atomic orbital symmetrical about the nucleus that is the most stable and lowest in energy, containing zero nodes, with only one existing per shell.

p Orbital

A dumbbell-shaped atomic orbital with two lobes and one node, symmetrical about an axis; three exist per shell starting in the second shell.

Node

An area within an orbital where there is a $0\%$ probability of finding an electron, representing forbidden territory and instability.

d Orbital

An atomic orbital typically consisting of four lobes in a cloverleaf shape with two nodal planes; five exist per shell starting in the third shell.

Core Electrons

Electrons housed in inner shells (such as the 1s shell) that are tucked inside the atom and not physically accessible for bond formation.

Valence Electrons

Electrons located in the outermost shell of an atom that are physically accessible to interact and form bonds with other atoms.

Constructive Interference

The reinforcement of electron wave amplitudes when atomic orbitals overlap in sync, resulting in a stable bonding molecular orbital.

Bonding Orbital

A lower-energy, more stable molecular orbital formed when overlapping atomic orbitals concentrate electronic density between two nuclei.

Antibonding Orbital

A higher-energy, less stable molecular orbital containing a node directly between two nuclei that counteracts bond formation.

Aufbau Principle

The rule stating that electrons will fill and occupy the lowest energy orbitals first.

Pauli Exclusion Principle

The rule stating that a maximum of two electrons can occupy any single orbital.

sp^3 Hybridized Orbitals

Four degenerate, equal-energy orbitals formed in a second-shell atom by blending one s orbital and three p orbitals.

Tetrahedron

The optimum three-dimensional electronic geometry adopted by four $sp^3$ hybridized orbitals to maximize separation, featuring bond angles of $109.5^\text{o}$.

Percentage s Character

The relative proportion of s orbital contribution in a set of hybrid orbitals, which equals 25\text{\null}\% in $sp^3$ hybridized orbitals.