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A theory of chemical bonding based upon the postulated existence of molecular orbitals.

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Flotation

Method by which hydrophobic (water-repelling) particles of an ore are separated from hydrophilic (water-attracting) particles of a metallurgical pretreatment process.

Lewis Dot Formula (Electron Dot Formula)

Representation of the core of a molecule, ion or formula unit by showing atomic symbols and only outer shell electrons.

Metal

An element below and to the left of the stepwise division (metalloids) in the upper right corner of the periodic table, about 80% of the known elements are metals.

Buret

A piece of volumetric glassware, usually graduated in 0.1-mL intervals, that is used to deliver solutions to be used in titrations in a quantitative (dropwise) manner.

How to make crystal glass

From history we know that the idea of creating crystal belongs to the British: they were the first to add lead oxides to the charge material, and as a result got glass with unusual “voice”, transparency and sparkling faces. Classical crystal contains 24% of lead oxide, but there are products with a higher content of up to 30%.

Manometer

A two-armed barometer.

Combustible

Classification of liquid substances that will burn on the basis of flash points. A combustible liquid means any liquid having a flash point at or above 37.8°C (100°F) but below 93.3°C (200°F), except any mixture having components with flash points of 93.3°C (200°F) or higher, the total of which makes up 99 percent or more of the total volume of the mixture.

Coordination Number

In describing crystals, the number of nearest neighbours of an atom or ion. The number of donor atoms coordinated to a metal.

Isomorphous

Refers to crystals having the same atomic arrangement.

Endothermic

Describes processes that absorb heat energy.