Columbia Encyclopedia

Search results

500 results found

cation

(Encyclopedia)cation kătˌīˈən [key], atom or group of atoms carrying a positive charge. The charge results because there are more protons than electrons in the cation. Cations can be formed from a metal by oxi...

Tibetan art and architecture

(Encyclopedia)Tibetan art and architecture have been almost entirely religious in character (see Tibetan Buddhism). The art of Tibetan Lamaism retains strong elements drawn from the forms of both Hinduism and Buddh...

hydrogen chloride

(Encyclopedia)hydrogen chloride, chemical compound, HCl, a colorless, poisonous gas with an unpleasant, acrid odor. It is very soluble in water and readily soluble in alcohol and ether. It fumes in moist air. It is...

hydrolysis

(Encyclopedia)hydrolysis hīdrŏlˈĭsĭs [key], chemical reaction of a compound with water, usually resulting in the formation of one or more new compounds. The most common hydrolysis occurs when a salt of a weak ...

protonation

(Encyclopedia)protonation prōˈtənāˌshən [key], in chemistry, addition of a proton to an atom, molecule, or ion. The proton is the nucleus of the hydrogen atom; the positive hydrogen ion, H+, consists of a sin...

adenine

(Encyclopedia)adenine ădˈənĭn, –nīn, –nēn [key], organic base of the purine family. Adenine combines with the sugar ribose to form adenosine, which in turn can be bonded with from one to three phosphoric ...

phosphoric acid

(Encyclopedia)phosphoric acid, any one of three chemical compounds made up of phosphorus, oxygen, and hydrogen (see acids and bases). The most common, orthophosphoric acid, H3PO4, is usually simply called phosphori...

Boyle, Robert

(Encyclopedia)Boyle, Robert, 1627–91, Anglo-Irish physicist and chemist. The seventh son of the 1st earl of Cork, he was educated at Eton and on the Continent and conducted most of his researches at his own labor...

nucleotide

(Encyclopedia)nucleotide no͞oˈklēətīdˌ, nyo͞oˈ– [key], organic substance that serves as a monomer in forming nucleic acids. Nucleotides consist of either a purine or a pyrimidine base, a ribose or deoxyri...

hydrogen cyanide

(Encyclopedia)hydrogen cyanide, HCN, colorless, volatile, and extremely poisonous chemical compound whose vapors have a bitter almond odor. It melts at −14℃ and boils at 26℃. It is miscible in all proportions...