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Assumes that electron pairs are arranged around the central element of a molecule or polyatomic ion so that there is maximum separation (and minimum repulsion) among regions of high electron density.

 

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Heterogeneous Equilibria

Equilibria involving species in more than one phase.

Gangue

Sand, rock, and other impurities surrounding the mineral of interest in an ore.

Period

The elements in a horizontal row of the periodic table.

Boyle's Law

At constant temperature the volume occupied by a definite mass of a gas is inversely proportional to the applied pressure.

Cell Potential

Potential difference, Ecell, between oxidation and reduction half-cells under nonstandard conditions.

 

Critical Pressure

The pressure required to liquefy a gas (vapor) at its critical temperature.

Heisenberg Uncertainty Principle

It is impossible to determine accurately both the momentum and position of an electron simultaneously.

Saturated Hydrocarbons

Hydrocarbons that contain only single bonds. They are also called alkanes or paraffin hydrocarbons.

Molality

Concentration expressed as number of moles of solute per kilogram of solvent.

Beta Particle

Electron emitted from the nucleus when a neuton decays to a proton and an electron.

Solute

The dispersed (dissolved) phase of a solution.

Gem-dimethyl group

Two methyl groups of the same carbon atom.

Chemical Hygiene Officer (CHO)

A person or employee who is qualified by training or experience to provide technical guidance in the development and implementations of the provisions of a Chemical Hygiene Plan (CHP)

Conjugated Double Bonds

Double bonds that are separated from each other by one single bond -C=C-C=C-.

Heat of Fusion

The amount of heat required to melt one gram of solid at its melting point with no change in temperature. Usually expressed in J/g. The molar heat of fusion is the amount of heat required to melt one mole of a solid at its melting point with no change in temperature and is usually expressed in kJ/mol.

Dimer

Molecule formed by combination of two smaller (identical) molecules.

Magnetic Quantum Number (mc)

Quantum mechanical solution to a wave equation that designates the particular orbital within a given set (s, p, d, f ) in which a electron resides.

Nucleons

Particles comprising the nucleus, protons and neutrons.

Alpha Particles

A helium nucleus.

Evaporization

Vaporization of a liquid below its boiling point.