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organic chemistry

(Encyclopedia)organic chemistry, branch of chemistry dealing with the compounds of carbon. While it is only the fourteenth most common element on earth, carbon forms by far the greatest number of different compound...

organic farming

(Encyclopedia)organic farming, the practice of growing plants—especially for fruits and vegetables, but for ornamentals as well—without the use of synthetic pesticides, herbicides, and fertilizers, or of raisin...

organic food

(Encyclopedia)organic food, food raised without chemicals and processed without additives. Under standards adopted by the U.S. Agriculture Dept. (USDA) in 2000 and fully effective in 2002, synthetic fertilizers and...

flint, mineral

(Encyclopedia)flint, variety of quartz that commonly occurs in rounded nodules and whose crystal structure is not visible to the naked eye. Flint is dark gray, smoky brown, or black in color; pale gray flint is cal...

asbestos, mineral

(Encyclopedia)asbestos, common name for any of a variety of silicate minerals within the amphibole and serpentine groups that are fibrous in structure and more or less resistant to acid and fire. Chrysotile asbesto...

mineral, dietary

(Encyclopedia)mineral, dietary, any of a group of inorganic elements that are essential to humans and animals for normal body function. In nutrition, minerals are those elements for which the body's requirement is ...

mineral water

(Encyclopedia)mineral water, spring water containing various mineral salts, especially the carbonates, chlorides, phosphates, silicates, sulfides, and sulfates of calcium, iron, lithium, magnesium, potassium, sodiu...

Mineral Wells

(Encyclopedia)Mineral Wells, city (1990 pop. 14,870), Palo Pinto and Parker counties, N Tex.; inc. 1882. Aluminum products, bottled mineral water, clothing, and pharmaceuticals are produced, and there is gas proces...

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