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QUANTITATIVE ANALYSIS

is the term applied to the methods used for determining the amount of each constituent of any substance,

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QUEBCITIN

A brown crystalline substance of meltingpoint 3130 C., soluble in alkaline solutions and used in dyeing. It is prepared from quercitrin.

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QUERCITRON

The powdered bark of Quercus tinctoria, the extract of which contains quercitrin together with other substances used in tanning and in dyeing textiles.

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QUINIC ACID

A white crystalline substance found in coffee beans, quinine bark, the common holly, and the leaves of some conifers and the cedar; soluble in water and alcohol; meltingpoint, j6o degrees C.

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QUILLAYA

The bark of Quillaya saponc.ria, from Bolivia, Peru, and Chili, which yields a soapy kind of infusion containing saponin which is used for washing, as a foam producer in soft drinks, for shampooing, and as an emulsifier.

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QUINONES

A group of yellow compounds used in dyestuffs, obtained from benzene and its derivatives, by methods which replace 2 atoms of hydrogen by 2 of oxygenfor example, quinone 2, which is prepared from a solution of quinol by thp, addition of chromic acid.

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QUASSIA WOOD

comes from a tree which grows in Jamaica and the West Indies. It contains about 003 per cent, of a very bitter crystalline substance named quassiin, which is soluble in alcohol and to a smaller extent in water. Infusions of the wood are used in medicine and as a bitter.

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QUEBRACHO EXTRACT,

used in tanning and dyeing as a substitute for catechu and sumach, is obtained from the wood of trees which grow abundantly in Brazil and the River Plate districts of Argentine and Paraguay. The dry extract contains about 65 per cent, tannin. The production for 1919 amounted to upwards of 170,000 tons.

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QUINOLINE

A colourless, highly refractive liquid of peculiar characteristic odour, present in coal tar, and produced synthetically from aniline. It is a tertiary amine which is soluble in water and alcohol, boils at 239 degrees C., has a sp. gr. ro8, and is used in medicine and for preserving anatomical specimens.

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QUALITATIVE analysis

is the term applied to the methods used for ascertaining the nature of the constituents of substances.

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