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sublimation, in chemistry

(Encyclopedia)sublimation sŭblĭmāˈshən [key], change of a solid substance directly to a vapor without first passing through the liquid state. The term is also used to describe the reverse process of the gas ch...

capillary

(Encyclopedia)capillary kăpˈəlĕrˌē [key], microscopic blood vessel, smallest unit of the circulatory system. Capillaries form a network of tiny tubes throughout the body, connecting arterioles (smallest arter...

flame

(Encyclopedia)flame, phenomenon associated with the chemical reaction of a gas that has been heated above its kindling temperature with some other gas, usually atmospheric oxygen (see combustion). The heat and ligh...

aluminum

(Encyclopedia)aluminum ălˌyo͞omĭnˈēəm [key], metallic chemical element; symbol Al; at. no. 13; at. wt. 26.98154; m.p. 660.37℃; b.p. 2,467℃; sp. gr. 2.6989 at 20℃; valence +3. Aluminum is a silver-white...

molecule

(Encyclopedia)molecule mŏlˈəkyo͞ol [key] [New Lat.,=little mass], smallest particle of a compound that has all the chemical properties of that compound. A single atom is usually not referred to as a molecule, a...

Nernst, Walther Hermann

(Encyclopedia)Nernst, Walther Hermann välˈtər hĕrˈmän nĕrnst [key], 1864–1941, German physicist and chemist, a founder of modern physical chemistry. After doing outstanding research on osmotic pressure and...

Liebig, Justus, Baron von

(Encyclopedia)Liebig, Justus, Baron von yo͝osˈto͝os bärônˈ fən lēˈbĭkh [key], 1803–73, German chemist. As professor at Giessen (1824–52), he was among the first to establish a chemical teaching labora...

mercaptan

(Encyclopedia)mercaptan thīˈōl [key], any of a class of organic compounds containing the group –SH bonded to a carbon atom. The volatile low-molecular-weight mercaptans have disagreeable odors. Mercaptans are ...

mass number

(Encyclopedia)mass number, often represented by the symbol A, the total number of nucleons (neutrons and protons) in the nucleus of an atom. All atoms of a chemical element have the same atomic number (number of pr...

Chauvin, Yves

(Encyclopedia)Chauvin, Yves, 1930–2015, French chemist, b. Menen, Belgium, grad. Lyon School of Chemistry, Physics, and Electronics (CPE), 1954. Chauvin was a research engineer (1960–91) and then research direc...