Metals, Light

**Definition:** Metals with low specific gravity, typically smaller than 5, characterized by a single valence (1, 2, or 3), a simple spectrum, strong electromotive force (positive), and colorless compounds. (From Grant & Hackh's Chemical Dictionary, 5th ed)

**Tree numbers:** - D01.268.557 - D01.552.547

**Synonyms:** - Light Metals