Columbia Encyclopedia

Search results

500 results found

mole, in chemistry

(Encyclopedia)mole, in chemistry, a quantity of particles of any type equal to Avogadro's number, or 6.02×1023 particles. One gram-molecular weight of any molecular substance contains exactly one mole of molecules...

dispersion, in chemistry

(Encyclopedia)dispersion, in chemistry, mixture in which fine particles of one substance are scattered throughout another substance. A dispersion is classed as a suspension, colloid, or solution. Generally, the par...

precipitation, in chemistry

(Encyclopedia)precipitation, in chemistry, a process in which a solid is separated from a suspension, sol, or solution. In a suspension such as sand in water the solid spontaneously precipitates (settles out) on st...

earth, in chemistry

(Encyclopedia)earth, in chemistry, metallic oxide not readily reducible by chemical means, e.g., alkaline earths, rare earths, and alumina. The name is also applied to certain absorbent clays, e.g., fuller's earth,...

Æthelmar of Valence

(Encyclopedia)Æthelmar of Valence: see Aymer of Valence. ...

inorganic chemistry

(Encyclopedia)inorganic chemistry, the study of all the elements and their compounds with the exception of carbon and its compounds, which fall under the category of organic chemistry. Inorganic chemistry investiga...

physical chemistry

(Encyclopedia)physical chemistry, branch of science that combines the principles and methods of physics and chemistry. It provides a fundamental theoretical and experimental basis for all of chemistry, including or...

Aymer of Valence

(Encyclopedia)Aymer of Valence āˈmər, vəlĕnsˈ, väläNsˈ [key], d. 1260, bishop of Winchester; son of Isabella (widow of King John of England) and Hugh X, count of La Marche. He was thus half-brother of King...