Resonance

Valence shell electron-pair repulsion

VSEPR full form

Predicts geometries around atoms in a molecule

What does the VSEPR model do?

By minimizing electron-group repulsions

How does the VSEPR predicts geometries around atoms in a molecule?

Electron group

Results in giving the molecule a 3D shape by arranging around an atom as far apart as possible

May be a lone pair, a single bond, a double bond, or a triple bond

Each count as one group because they represent a group electrons on the same spatial location

Electron geometry

The 3D shape results from the electron groups around an atom arranging themselves to be as far as possible.

Molecular structure

The arrangement of atoms in a molecule or ion.

Looks only at the bonded atoms within the molecules ignoring any non-bonding electrons.

Thiocyanate

[SCN]-

1) Zero 2) Least non-zeroes 3) Adjacent atoms to have opposite signs 4) Negative formal charge on the most electronegative atom is preferred

Guidelines of the Lewis structures with charges

Anesthetic

Any agent that produces a loss of sensation, including pain, by acting on the nervous system.

Nitrous oxide (N2O)

An anesthetic in minor surgeries such as the routine extraction of the wisdom teeth. Commonly known as the laughing gas.

shorter, stronger

The double bond between the two atoms is _______ and ________ than the single bond between the same two atoms

Resonance

A concept used when no single Lewis structure represents a molecule

The actual structure is an average of multiple valid Lewis structures

Resonance forms

Different Lewis structures for the same molecule that have the same arrangement of atoms but different electron placements.

Resonance hybrid

The real electronic structure of the molecule. An average of all the resonance forms.

Double-headed arrow

A symbol that indicates that Lewis structures are resonance forms