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free radical

(Encyclopedia)free radical, in chemistry, a molecule or atom that contains an unpaired electron but is neither positively nor negatively charged. Free radicals are usually highly reactive and unstable. They are pro...

Gross, David Jonathan

(Encyclopedia)Gross, David Jonathan, 1941–, American particle physicist, b. Washington, D.C., Ph.D. Univ. of California, Berkeley, 1966. Gross was a professor at Princeton from 1969 to 1997, when he joined the fa...

Grubbs, Robert Howard

(Encyclopedia)Grubbs, Robert Howard, 1942–2021, American chemist, b. near Possum Trot, Ky., Univ. of Florida (B.S., 1963; M.S., 1965), Columbia, Univ. (Ph.D, 1968)....

radioactivity

(Encyclopedia) CE5 Effects of a magnetic field on the products of radioactivity CE5 Disintegration series: Radioactive decay of radium-226 into lead-206 radioactivity, spontaneous disintegration or decay of t...

muon

(Encyclopedia)muon myo͞oˈŏn [key], elementary particle heavier than an electron but lighter than other particles having nonzero rest mass. The name muon is derived from mu meson, the former name of the particle....

formula weight

(Encyclopedia)formula weight, in chemistry, a quantity computed by multiplying the atomic weight (in atomic mass units) of each element in a formula by the number of atoms of that element present in the formula, an...

anion

(Encyclopedia)anion ănˈīˌən [key], atom or group of atoms carrying a negative charge. The charge results because there are more electrons than protons in the anion. Anions can be formed from nonmetals by reduc...

Fuchs, Klaus Emil

(Encyclopedia)Fuchs, Klaus Emil fo͝oks, fo͞oks [key], 1912–88, British physicist and Communist spy, b. Germany. In 1933 he fled Germany for England, where he completed his education. Interned (1940–41) in Can...

flerovium

(Encyclopedia)flerovium, artificially produced radioactive chemical element; symbol Fl; at. no. 114; mass number of most stable isotope 289; m.p., b.p., sp. gr., and valence unknown. Situated in Group 14 of the per...

second

(Encyclopedia)second, abbr. sec or s, fundamental unit of time in all systems of measurement. In practical terms, the second is 1/60 of a minute, 1/3,600 of an hour, or 1/86,400 of a day. Since the length of the da...
 

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