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europium

(Encyclopedia)europium yo͝orōˈpēəm [key] [from Europe], metallic chemical element; symbol Eu; at. no. 63; at. wt. 151.964; m.p. about 820℃; b.p. about 1,600℃; sp. gr. 5.25 at 25℃; valence +2 or +3. Europ...

inert gas

(Encyclopedia)inert gas or noble gas, any of the elements in Group 18 of the periodic table. In order of increasing atomic number they are: helium, neon, argon, krypton, xenon, and radon. They are colorless, odorle...

erbium

(Encyclopedia)erbium ûrˈbēəm [key] [from Ytterby, a town in Sweden], metallic chemical element; symbol Er; at. no. 68; at. wt. 167.259; m.p. 1,529℃; b.p. 2,863℃; sp. gr. 9.05 at 25℃; valence +3. Erbium is...

meitnerium

(Encyclopedia)meitnerium mītnĭrˈēəm [key], artificially produced radioactive chemical element; symbol Mt; at. no. 109; mass number of most stable isotope 276; m.p., b.p., sp. gr., and valence unknown. Situated...

asthma

(Encyclopedia)asthma ăzˈmə, ăsˈ– [key], chronic inflammatory respiratory disease characterized by periodic attacks of wheezing, shortness of breath, and a tight feeling in the chest. A cough producing sticky...

nobelium

(Encyclopedia)nobelium nōbēˈlēəm [key], artificially produced radioactive chemical element; symbol No; at. no. 102; mass no. of most stable isotope 259; m.p. 827℃; b.p. and density unknown; valence +2, +3. I...

osmium

(Encyclopedia)osmium ŏzˈmēəm [key], metallic chemical element; symbol Os; at. no. 76; at. wt. 190.23; m.p. 3,045±30℃; b.p. 5,027±100℃; sp. gr. 22.57 at 20℃; valence usually +0 to +8. Osmium is a very ha...

thulium

(Encyclopedia)thulium tho͞oˈlēəm [key] [from Thule, an ancient name for Scandinavia], metallic chemical element; symbol Tm; at. no. 69; at. wt. 168.93421; m.p. about 1,545℃; b.p. 1,947℃; sp. gr. 9.3; valenc...

terbium

(Encyclopedia)terbium tûrˈbēəm [key] [from Ytterby, a village in Sweden], metallic chemical element; symbol Tb; at. no. 65; at. wt. 158.92535; m.p. 1,356℃; b.p. 3,123℃; sp. gr. about 8.25; valence +3 or +4....

Quemoy

(Encyclopedia)Quemoy kĭmoiˈ [key], Chin. Chinmen, Kinmen, or Jinmen, Taiwanese island group (2010 pop. 56,703), Taiwan Strait, just off Fujian prov., China, and c.150 mi (240 km) W of Taiwan. The group consists o...