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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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Octahedral

A term used to describe molecules and polyatomic ions that have one atom in the center and six atoms at the corners of a octahedron.

xylan

The pentosan occurring in woody tissue that hydrolyzes to xylose: used as a source of furfural.

Nickel-cadmium cell (Nicad battery)

A dry cell in which the anode is Cd, the cathode is NiO2, and the electrolyte is basic.

History of diamonds

Diamond has been known for about 5 thousand years. Historians suggest that it was first discovered in India in river placers. It has long been credited with magical properties, and the largest famous crystals and products from them are shrouded in a halo of mystical legends.

Domain

A cluster of atoms in a ferromagnetic substance, all of which align in the same direction in the presence of an external magnetic field.

Specific Rate Constant

An experimentally determined (proportionality) constant, which is different for different reactions and which changes only with temperature, k in the rate-law expression: Rate = k [A] x [B]v.

Composition Stoichiometry

Descibes the quantitative (mass) relationships among elements in compounds.

Standard Reaction

A reaction in which the numbers of moles of reactants shown in the balanced equation, all in their standard states, are completely converted to the numbers of moles of products shown in the balanced equation, also sall at their standard state.

Hydrogen Bond

A fairly strong dipole-dipole interaction (but still considerably weaker than the covalent or ionic bonds) between molecules containing hydrogen directly bonded to a small, highly electronegative atom, such as N, O, or F.

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