Vsepr Theory

Sulfur tetrafluoride

Sulfur tetrafluoride

________ has a steric number of 5.

VSEPR theory

________ therefore views repulsion by the lone pair to be greater than the repulsion by a bonding pair.

electron pairs

If there are 3 ________ surrounding the central atom, their repulsion is minimized by placing them at the vertices of an equilateral triangle centered on the atom.

1939

The idea of a correlation between molecular geometry and number of valence electron pairs (both shared and unshared pairs) was originally proposed in ________ by Ryutaro Tsuchida in Japan, [7] and was independently presented in a Bakerian Lecture in 1940 by Nevil Sidgwick and Herbert Powell of the University of Oxford.

Lone pair

________- ________ (lp- lp) repulsions are considered stronger than ________- bonding pair (lp- bp) repulsions, which in turn are considered stronger than bonding pair- bonding pair (bp- bp) repulsions, distinctions that then guide decisions about overall geometry when 2 or more non- equivalent positions are possible.

number of electron pairs

The ________ in the valence shell of a central atom is determined after drawing the Lewis structure of the molecule, and expanding it to show all bonding groups and lone pairs of electrons.

VSEPR theory

________ is used to predict the arrangement of electron pairs around central atoms in molecules, especially simple and symmetric molecules.

electron pairs

The ________ (or groups if multiple bonds are present) are assumed to lie on the surface of a sphere centered on the central atom and tend to occupy positions that minimize their mutual repulsions by maximizing the distance between them.

electron pair

A(n) ________ in an axial position has three close equatorial neighbors only 90° away and a fourth much farther at 180°, while an equatorial electron pair has only two adjacent pairs at 90° and two at 120°.

electron pair

The bonding ________ shared in a sigma bond with an adjacent atom lies further from the central atom than a nonbonding (lone) pair of that atom, which is held close to its positively charged nucleus.