Sulfur is an element with 16 neutrons. Sulfur also has 16 protons and 16 electrons. This results in an atomic number of 16 and an atomic mass of 32.
Sulfur is a yellow, brittle, odorless solid. It has been known since ancient times but was not recognized as an element until 1777, based on the work of Antoine Lavoisier. The name sulfur comes from the Latin word sulphurium, which means brimstone. Sulfur is used in the formation of several compounds. While sulfur itself is odorless, when combined to form hydrogen sulfide (H2S), it smells like rotten eggs. Sulfuric acid (H2SO4) is used in fertilizers, gunpowder and insecticides. Sulfur dioxide (SO2) is used as a bleaching agent.