Columbia Encyclopedia

Search results

500 results found

osmium

(Encyclopedia)osmium ŏzˈmēəm [key], metallic chemical element; symbol Os; at. no. 76; at. wt. 190.23; m.p. 3,045±30℃; b.p. 5,027±100℃; sp. gr. 22.57 at 20℃; valence usually +0 to +8. Osmium is a very ha...

virology

(Encyclopedia)virology, study of viruses and their role in disease. Many viruses, such as animal RNA viruses and viruses that infect bacteria, or bacteriophages, have become useful laboratory tools in genetic studi...

biochemistry

(Encyclopedia)biochemistry, science concerned chiefly with the chemistry of biological processes; it attempts to utilize the tools and concepts of chemistry, particularly organic and physical chemistry, for elucida...

chromium

(Encyclopedia)chromium krōˈmēəm [key] [Gr.,=color], metallic chemical element; symbol Cr; at. no. 24; at. wt. 51.9961; m.p. about 1,857℃; b.p. 2,672℃; sp. gr. about 7.2 at 20℃; valence +2, +3, +6. Chromiu...

bromine

(Encyclopedia)bromine brōˈmēn, –mĭn [key] [Gr.,=stench], volatile, liquid chemical element; symbol Br; at. no. 35; at. wt. 79.904; m.p. –7.2℃; b.p. 58.78℃; sp. gr. of liquid 3.12 at 20℃; density of va...

catalyst

(Encyclopedia)catalyst, substance that can cause a change in the rate of a chemical reaction without itself being consumed in the reaction; the changing of the reaction rate by use of a catalyst is called catalysis...

classification

(Encyclopedia)CE5 classification, in biology, the systematic categorization of organisms into a coherent scheme. The original purpose of biological classification, or systematics, was to organize the vast number...

curry

(Encyclopedia)curry [Malayalam], condiment much used in India and elsewhere in Asia and the Middle East, in combination with rice, meat, and a variety of other dishes. It is compounded of such spices as turmeric, f...

Lynen, Feodor

(Encyclopedia)Lynen, Feodor fāōˈdôr lēˈnən [key], 1911–79, German biochemist, grad. Univ. of Munich (Ph.D. 1937). He began teaching at the Max Planck Institute for Cell Chemistry in Munich in 1947. His res...

lead acetate

(Encyclopedia)lead acetate, chemical compound, a white crystalline substance with a sweetish taste. Like other lead compounds, it is very poisonous. Lead acetate is soluble in water and glycerin. With water it form...