uranium

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, +5, or +6.

Sections in this article:

• Introduction
• Discovery and Uses
• Natural Occurrence and Processing
• Isotopes and Radioactive Decay
• Properties

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