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niobium

(Encyclopedia)niobium nīōˈbēəm [key], metallic chemical element; symbol Nb; at. no. 41; at. wt. 92.90638; m.p. about 2,468℃; b.p. 4,742℃; sp. gr. 8.57 at 20℃; valence +2, +3, +4, or +5. Niobium is a rare...

neon

(Encyclopedia)neon nēˈŏn [key] [Gr.,=new], gaseous chemical element; symbol Ne; at. no. 10; at. wt. 20.1797; m.p. −248.67℃; b.p. −246.048℃; density 0.8999 grams per liter at STP; valence 0. Neon is a col...

neptunium

(Encyclopedia)neptunium nĕpto͞oˈnēəm [key], radioactive chemical element; symbol Np; at. no. 93; mass number of most stable isotope 237; m.p. about 640℃; b.p. 3,902℃ (estimated); sp. gr. 20.25 at 20℃; va...

cadmium

(Encyclopedia)cadmium kădˈmēəm [key] [from cadmia, Lat. for calamine, with which cadmium is found associated], metallic chemical element; symbol Cd; at. no. 48; at. wt. 112.411; m.p. 321℃; b.p. 765℃; sp. gr...

biochemistry

(Encyclopedia)biochemistry, science concerned chiefly with the chemistry of biological processes; it attempts to utilize the tools and concepts of chemistry, particularly organic and physical chemistry, for elucida...

carbonyl group

(Encyclopedia)carbonyl group kärˈbənĭl [key], in chemistry, functional group that consists of an oxygen atom joined by a double bond to a carbon atom. The carbon atom is joined to the remainder of the molecule ...

spectrum

(Encyclopedia)CE5 Dispersion of white light by a triangular prism spectrum, arrangement or display of light or other form of radiation separated according to wavelength, frequency, energy, or some other propert...

Kursk

(Encyclopedia)Kursk ko͝orsk [key], city (1989 pop. 424,000), capital of Kursk region, W European Russia, at the confluence of the Tuskor and Seim rivers. An important rail junction, it has machine, chemical, and s...

Maribor

(Encyclopedia)Maribor mäˈrĭbôr [key], Ger. Marburg, city (1991 pop. 103,961), in Slovenia, on the Drava River. It is a heavy industrial center with chemical, engineering, and electrical industries. Known as ear...

Mulliken, Robert Sanderson

(Encyclopedia)Mulliken, Robert Sanderson, 1896–1986, American chemist, b. Newburyport, Mass., Ph.D. Univ. of Chicago, 1921. Mulliken taught at New York Univ. from 1926 to 1928 and then at the Univ. of Chicago fro...