The simplest sulphur anion is the S2- ion, which is also called sulphide. Its electron configuration is 1s2 2s2 2p6 3s2 3p6. A neutral sulphur atom has 16 electrons, but when it forms an ion, it gets two more electrons, bringing the total number of electrons to 18.
In S2-, sulphur forms a negative ion, also called an anion. This means that the original electron configuration of neutral sulphur needs to be changed by adding two ions.
Sulfide is a very strong base. Because of hydrolysis, all sulphide solutions in water are also bases. All solutions of sulphide in water smell like rotten eggs because of this process. When sulphide is mixed with water, it takes on one proton from the H2O.
This makes one molecule of SH- and one molecule of OH-. When sulphide is mixed with an acid, hydrogen sulphide (H2S) and a metal salt are made.
Many important metal ores, like argentite, molybdenite, galena, and cinnabar, contain sulphide. Argentite is a sulphide of silver. Galena is a sulphide of lead. Cinnabar is a sulphide of mercury. And molybdenite is a sulphide of molybdenum. Infrared lasers often use lead sulfite.