The Lewis structure for H2S features a central sulfur atom, written as just the letter S, single-bonded to two hydrogen atoms, each represented by the letter H. There are four dots representing two lone pairs of electrons drawn above or below the sulfur atom.
H2S is the chemical formula for hydrogen sulfide, an inorganic, flammable gas that smells similar to rotten eggs. Although the Lewis structure of hydrogen sulfide closely resembles that of water, or H2O, the two substances have very different chemical properties. Sulfur is a more electronegative element than oxygen, which results in hydrogen sulfide molecules being less polar than water molecules. As a result, the intermolecular forces keeping the atoms of a hydrogen sulfide molecule together are weak compared to water, and hydrogen sulfide boils at much lower temperatures. The boiling point of water is 100 degrees Celsius, while hydrogen sulfide boils at only -60.7 degrees Celsius.
Hydrogen sulfide is a natural component of volcanic gases, crude petroleum and other natural gases. The breakdown of organic matter produces hydrogen sulfide naturally, and bacteria found inside the human mouth and gastrointestinal tract are also able to produce the gas. Hydrogen sulfide does not have many commercial uses in itself, but it can be used to create pure sulfur, which is very commercially useful.