Sulfide ion
Charge: 2- · Type: Anion · Molar mass: 32.06 g/mol
Made of: sulfur
How it forms
Sulfur takes two electrons from electropositive metals to complete its outer shell, forming S2-. In water the ion reacts to form HS- and hydroxide, which is why sulfide solutions smell of hydrogen sulfide and feel slippery.
Naming note
S2- is the sulfide ion. Hydrogen sulfide (H2S) is a covalent compound, not a salt of the sulfide ion, though it is named as if it were.
Examples in compounds
Iron(II) sulfide
Zinc sulfide
Hydrogen sulfide