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potassium

(Encyclopedia)potassium pətăsˈēəm [key], a metallic chemical element; symbol K [Lat. kalium=alkali]; at. no. 19; at. wt. 39.0983; m.p. 63.25℃; b.p. 760℃; sp. gr. .862 at 20℃; valence +1. Potassium is a s...

symbol

(Encyclopedia)symbol, sign representing something that has an independent existence. The most important use of symbols is in language. To say so, however, does not solve the perennial philosophical questions as to ...

hydrogen

(Encyclopedia)hydrogen hīˈdrəjən [key] [Gr.,=water forming], gaseous chemical element; symbol H; at. no. 1; interval in which at. wt. ranges 1.00784–1.00811; m.p. −259.14℃; b.p. −252.87℃; density 0.08...

Yoshino, Akira

(Encyclopedia)Yoshino, Akira, 1948–, Japanese chemist, Ph.D. Osaka Univ., 2005. He was a researcher at Asahi Kasei Corp. from 1972 to 2017, when he became a professor at Meijo Univ., Nagoya, Japan. Akira received...

Fermi, Enrico

(Encyclopedia)Fermi, Enrico ĕnrēˈkō fĕrˈmē [key], 1901–54, American physicist, b. Italy. He studied at Pisa, Göttingen, and Leiden, and taught physics at the universities of Florence and Rome. He contribu...

rhodium

(Encyclopedia)rhodium rōˈdēəm [key], metallic chemical element; symbol Rh; at. no. 45; at. wt. 102.90550; m.p. about 1,966℃; b.p. 3,727±100℃; sp. gr. 12.41 at 20℃; valence +2, +3, +4, +5, or +6. Rhodium ...

anemia

(Encyclopedia)anemia ənēˈmēə [key], condition in which the concentration of hemoglobin in the circulating blood is below normal. Such a condition is caused by a deficient number of erythrocytes (red blood cell...

oxygen

(Encyclopedia)oxygen, gaseous chemical element; symbol O; at. no. 8; interval in which at. wt. ranges 15.99903–15.99977; m.p. −218.4℃; b.p. −182.962℃; density 1.429 grams per liter at STP; valence −2. T...

group

(Encyclopedia)group, in mathematics, system consisting of a set of elements and a binary operation a∘b defined for combining two elements such that the following requirements are satisfied: (1) The set is closed ...

sodium

(Encyclopedia)sodium, a metallic chemical element; symbol Na [Lat. natrium]; at. no. 11; at. wt. 22.98977; m.p. 97.81℃; b.p. 892.9℃; sp. gr. 0.971 at 20℃; valence +1. Sodium is a soft, silver-white metal. Ext...