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Prout, William

(Encyclopedia)Prout, William, 1785–1850, English chemist and physician. Prout's hypothesis, advanced in 1815–16, suggested that atomic weights of elements are multiples of that of hydrogen and that elements are...

Pelletier, Pierre Joseph

(Encyclopedia)Pelletier, Pierre Joseph pyĕr zhôzĕfˈ pĕlətyāˈ [key], 1788–1842, French chemist. With J. B. Caventou, he was cofounder of alkaloid chemistry and codiscoverer of quinine, strychnine, brucine,...

cyanide

(Encyclopedia)cyanide sīˈənīdˌ [key], chemical compound containing the cyano group, –CN. Cyanides are salts or esters of hydrogen cyanide (hydrocyanic acid, HCN) formed by replacing the hydrogen with a metal...

Gay-Lussac, Joseph Louis

(Encyclopedia)Gay-Lussac, Joseph Louis zhôzĕfˈ lwē gā-lüsäkˈ [key], 1778–1850, French chemist and physicist. He was professor in Paris at the Sorbonne, at the Polytechnic School, and at the Jardin des Pla...

Molina, Mario

(Encyclopedia)Molina, Mario (Mario José Molina-Pasquel y Henríquez), 1943–2020, Mexican chemist, Ph.D. Univ. of California, Berkeley, 1972. Molina was a professor at the Univ. of California, Irvine from 1975 to...

Lawrence Berkeley National Laboratory

(Encyclopedia)Lawrence Berkeley National Laboratory and Lawrence Livermore National Laboratory, scientific research centers run by the Univ. of California, located in Berkeley, Calif., and Livermore, Calif., respec...

Arianism

(Encyclopedia)Arianism ârˈēənĭzˌəm [key], Christian heresy founded by Arius in the 4th cent. It was one of the most widespread and divisive heresies in the history of Christianity. As a priest in Alexandria,...

function

(Encyclopedia)function, in mathematics, a relation f that assigns to each member x of some set X a corresponding member y of some set Y; y is said to be a function of x, usually denoted f(x) (read “f of x ”)....

sphere

(Encyclopedia)sphere, in geometry, the three-dimensional analogue of a circle. The term is applied to the spherical surface, every point of which is the same distance (the radius) from a certain fixed point (the ce...

pH

(Encyclopedia)pH, range of numbers expressing the relative acidity or alkalinity of a solution. In general, pH values range from 0 to 14. The pH of a neutral solution, i.e., one which is neither acidic nor alkaline...