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zirconium

(Encyclopedia)zirconium zərkōˈnēəm [key], metallic chemical element; symbol Zr; at. no. 40; at. wt. 91.224; m.p. about 1,852℃; b.p. 4,377℃; sp. gr. 6.5 at 20℃; valence +2, +3, or +4. Zirconium is a very ...

Zr

(Encyclopedia)Zr, symbol for the element zirconium. ...

hafnium

(Encyclopedia)hafnium hăfˈnēəm [key], metallic chemical element; symbol Hf; at. no. 72; at. wt. 178.49; m.p. about 2,227℃; b.p. 4,602℃; sp. gr. 13.31 at 20℃; valence +4. Hafnium is a lustrous, ductile, si...

Klaproth, Martin Heinrich

(Encyclopedia)Klaproth, Martin Heinrich märˈtēn hīnˈrĭkh kläpˈrōt [key], 1743–1817, German chemist. He is often referred to as the father of analytic chemistry. He recognized (1789) the presence of zirco...

magnalium

(Encyclopedia)magnalium măgnāˈlēəm [key], alloy of aluminum and about 5% magnesium. Although weak and soft in the elemental state, magnesium alloys with aluminum, manganese, zinc, tin, zirconium, and cerium to...

Berzelius, Jöns Jakob, Baron

(Encyclopedia)Berzelius, Jöns Jakob, Baron bərzēˈlēəs; Swed. yöns yäˈkôp bĕrsāˈlĭəs [key], 1779–1848, Swedish chemist, M.D. Univ. of Uppsala, 1802. He was noted for his work as teacher at the medic...

rare-earth metals

(Encyclopedia)rare-earth metals, in chemistry, group of metals including those of the lanthanide series and actinide series and usually yttrium, sometimes scandium and thorium, and rarely zirconium. Promethium, whi...

silicate

(Encyclopedia)silicate, chemical compound containing silicon, oxygen, and one or more metals, e.g., aluminum, barium, beryllium, calcium, iron, magnesium, manganese, potassium, sodium, or zirconium. Silicates may b...

titanium

(Encyclopedia)titanium tītāˈnēəm, tĭ– [key] [from Titan], metallic chemical element; symbol Ti; at. no. 22; at. wt. 47.867; m.p. 1,675℃; b.p. 3,260℃; sp. gr. 4.54 at 20℃; valence +2, +3, or +4. Titani...

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