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A molecular orbital higher in energy than any of the atomic orbitals from which it is derived, lends instability to a molecule or ion when populated with electrons, denoted with a star (*) superscript or symbol.

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Thermodynamics

The study of the energy transfers accompanying physical and chemical processes.

Peroxide

A compound containing oxygen in the -1 oxidation state. Metal peroxides contain the peroxide ion, O22

Distillation

The separation of a liquid mixture into its components on the basis of differences in boiling points. The process in which components of a mixture are separated by boiling away the more volitile liquid.

Autoionization

An ionization reaction between identical molecules.

Lewis Base

Any species that can make available a share in an electron pair.

Anion

A negative ion, an atom or goup of atoms that has gained one or more electrons.

 

van der Waals' Equation

An equation of state that extends the ideal gas law to real gases by inclusion of two empirically determined parameters, which are different for different gases.

Flammable

A liquid as defined by NFPD and DOT as having a flash point below 37.8°C (100°F).

Forbidden Zone

A relatively large energy separation between an insulator's highest filled electron energy band and the next higher energy vacant band. Beginning in the fourth energy level, a set of seven degenerate orbitals per energy level, higher in energy than s, p, and d orbitals of the same energy level.

Alpha (a) Particle

Helium ion with 2+ charge, an assembly of two protons and two neutrons.