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sulfate

(Encyclopedia)sulfate, chemical compound containing the sulfate (SO4) radical. Sulfates are salts or esters of sulfuric acid, H2SO4, formed by replacing one or both of the hydrogens with a metal (e.g., sodium) or a...

Stoicism

(Encyclopedia)Stoicism stōˈĭsĭzəm [key], school of philosophy founded by Zeno of Citium (in Cyprus) c.300 b.c. The first Stoics were so called because they met in the Stoa Poecile [Gr.,=painted porch], at Athe...

carbon monoxide

(Encyclopedia)carbon monoxide, chemical compound, CO, a colorless, odorless, tasteless, extremely poisonous gas that is less dense than air under ordinary conditions. It is very slightly soluble in water and burns ...

zinc

(Encyclopedia)zinc, metallic chemical element; symbol Zn; at. no. 30; at. wt. 65.38; m.p. 419.58℃; b.p. 907℃; sp. gr. 7.133 at 25℃; valence +2. Zinc is a lustrous bluish-white metal. It is found in Group 12 o...

water

(Encyclopedia)CE5 A. Water molecule (black circles represent valence-shell electrons) B. Structure of ice: Each oxygen atom (white circles) is bonded to four other oxygen atoms by hydrogen bonds, the hydrogen at...

gene

(Encyclopedia)gene, the structural unit of inheritance in living organisms. A gene is, in essence, a segment of DNA that has a particular purpose, i.e., that codes for (contains the chemical information necessary f...

insecticides

(Encyclopedia)insecticides, chemical, biological, or other agents used to destroy insect pests; the term commonly refers to chemical agents only. The liabilities of chemical insecticides have encouraged interest ...

silver

(Encyclopedia)silver, metallic chemical element; symbol Ag [Lat. argentum]; at. no. 47; at. wt. 107.8682; m.p. 961.93℃; b.p. 2,212℃; sp. gr. 10.5 at 20℃; valence +1 or +2. Pure silver is nearly white, lustrou...

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...

Beirut

(Encyclopedia)Beirut bāro͞otˈ [key], Arab. Bayrut, Fr. Beyrouth, city (1996 est. pop. 1,200,000), W Lebanon, capital of Lebanon, on the Mediterranean Sea, at the foot of the Lebanon Mts. Beirut is an important p...