Columbia Encyclopedia

Search results

276 results found

hydroxyl group

(Encyclopedia)hydroxyl group hīdrŏkˈsĭl [key], in chemistry, functional group that consists of an oxygen atom joined by a single bond to a hydrogen atom. An alcohol is formed when a hydroxyl group is joined by ...

Wurtz, Charles Adolphe

(Encyclopedia)Wurtz, Charles Adolphe shärl ädôlfˈ vürts [key], 1817–84, French chemist. He was professor at the Sorbonne (1852–75), at the Faculty of Medicine, Paris (1853–75), and at the Faculty of Scie...

nitrate

(Encyclopedia)nitrate, chemical compound containing the nitrate (NO3) radical. Nitrates are salts or esters of nitric acid, HNO3, formed by replacing the hydrogen with a metal (e.g., sodium or potassium) or a radic...

silicate

(Encyclopedia)silicate, chemical compound containing silicon, oxygen, and one or more metals, e.g., aluminum, barium, beryllium, calcium, iron, magnesium, manganese, potassium, sodium, or zirconium. Silicates may b...

Rochelle salt

(Encyclopedia)Rochelle salt, colorless to blue-white orthorhombic crystalline salt with a saline, cooling taste. It is also called Seignette salt after Pierre Seignette, an apothecary of La Rochelle, France, who wa...

Davy, Sir Humphry

(Encyclopedia)Davy, Sir Humphry, 1778–1829, English chemist and physicist. The son of a woodcarver, he received his early education at Truro and was apprenticed (1795) to a surgeon-apothecary at Penzance. While d...

depilatory

(Encyclopedia)depilatory dĭpĭlˈətôrˌē [key], substance used to remove hair. In preparing hides for tanning, lime is the chief depilatory. For the removal of superfluous hair from the human body, metal sulfid...

benzoic acid

(Encyclopedia)benzoic acid bĕnzōˈĭk [key], C6H5CO2H, crystalline solid organic acid that melts at 122℃ and boils at 249℃. It is the simplest aromatic carboxylic acid (see aryl group and carboxyl group). In ...

Carrel, Alexis

(Encyclopedia)Carrel, Alexis kärĕlˈ, kə– [key], 1873–1944, American surgeon and experimental biologist, b. near Lyons, France, M.D. Univ. of Lyons, 1900. Coming to the United States in 1905, he joined the s...

airglow

(Encyclopedia)airglow, faint diffuse illumination of the sky originating in the upper atmosphere. Although it occurs at all times of day throughout the upper atmosphere, it is most typically visible to an observer ...