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magnesite

(Encyclopedia)magnesite măgˈnəsīt [key], mineral, magnesium carbonate, MgCO3, white, yellow, or gray in color. It originates through the alteration of olivine or of serpentine by waters carrying carbon dioxide;...

oxide

(Encyclopedia)oxide, chemical compound containing oxygen and one other chemical element. Oxides are widely and abundantly distributed in nature. Water is the oxide of hydrogen. Silicon dioxide is the major componen...

respiration

(Encyclopedia)CE5 Respiratory system respiration, process by which an organism exchanges gases with its environment. The term now refers to the overall process by which oxygen is abstracted from air and is tran...

sodium bicarbonate

(Encyclopedia)sodium bicarbonate or sodium hydrogen carbonate, chemical compound, NaHCO3, a white crystalline or granular powder, commonly known as bicarbonate of soda or baking soda. It is soluble in water and ver...

calcination

(Encyclopedia)calcination kălˌsənāˈshən [key], in metallurgy, process of heating solid material to drive off volatile chemically combined components, e.g., carbon dioxide. It is sometimes a step in the extrac...

law of simple multiple proportions

(Encyclopedia)law of simple multiple proportions, in chemistry, the statement that when two or more elements form more than one compound, the ratio of the weights of one element that combine with a given weight of ...

Nyos, Lake

(Encyclopedia)Nyos, Lake nēōsˈ [key], freshwater lake in a volcanic crater in North-West prov., Cameroon, 15 mi (24 km) ENE of Wum. On Aug. 21, 1986, carbon dioxide gas was released from the mineral-saturated wa...

photosynthesis

(Encyclopedia)photosynthesis fōˌtōsĭnˈthəsĭs [key], process in which green plants, algae, and cyanobacteria utilize the energy of sunlight to manufacture carbohydrates from carbon dioxide and water in the pr...

dry ice

(Encyclopedia)dry ice: see carbon dioxide.

hiccup

(Encyclopedia)hiccup or hiccough, involuntary spasmodic contraction of the diaphragm followed by a sharp intake of air, which is abruptly stopped by a sudden, involuntary closing of the glottis (opening between the...