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darmstadtium

(Encyclopedia)darmstadtium, artificially produced radioactive chemical element; symbol Ds; at. no. 110; mass number of most stable isotope 281; m.p., b.p., sp. gr., and valence unknown. Situated in Group 10 of the ...

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...

uranium

(Encyclopedia)uranium yo͞orāˈnēəm [key], radioactive metallic chemical element; symbol U; at. no. 92; mass number of most stable isotope 238; m.p. 1,132℃; b.p. 3,818℃; sp. gr. 19.1 at 25℃; valence +3, +4...

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...

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 ...

oxide

(Encyclopedia)oxide, chemical compound containing oxygen and one other chemical element. Oxides are widely and abundantly distributed in nature. Water is the oxide of hydrogen. Silicon dioxide is the major componen...

bismuth

(Encyclopedia)bismuth bĭzˈməth [key] [Ger. Weisse Masse=white mass], metallic chemical element; symbol Bi; at. no. 83; at. wt. 208.98040; m.p. 271.3℃; b.p. about 1,560℃; sp. gr. 9.75 at 20℃; valence +3 or ...

lutetium

(Encyclopedia)lutetium, formerly lutecium both: lo͞otēˈshēəm [key], metallic chemical element; symbol Lu; atomic number 71; at. wt. 174.9668; m.p. about 1,663℃; b.p. about 3,395℃; sp. gr. 9.835 at 25℃; v...

flerovium

(Encyclopedia)flerovium, artificially produced radioactive chemical element; symbol Fl; at. no. 114; mass number of most stable isotope 289; m.p., b.p., sp. gr., and valence unknown. Situated in Group 14 of the per...

battery, electric

(Encyclopedia) CE5 Lead storage cell: At the lead-dioxide electrode, electrons from the circuit combine with lead dioxide and sulfuric acid to form lead sulfate and water. At the spongy-lead electrode, lead react...
 

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