Brimstone is sulfur, and sulfur is an element. Atomic number 16; atomic weight 32.066; melting point (rhombic) 112.8°C, (monoclinic) 119.0°C; boiling point 444.6°C; specific gravity (rhombic) 2.07, (monoclinic) 1.957; valence 2, 4, 6.
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