sulfur (Sulphur) is a chemical element that has an atomic number 16. It is represented through the symbol S. Its standard atomic weight is 32.06. In the periodic table, it can be found in group 16 (chalcogens) and 3rd period. It is a p-block element and non-metallic. The electronic configuration of sulfur is [Ne] 3s2 3p4 and it is a multivalent element. The electronegativity of sulfur is 2.58 (Pauling scale), and Oxidation states maybe −2, −1, 0, +1, +2, +3, +4, +5, +6 depending on the bonding atom. At standard temperature and pressure, it is solid (microcrystals) and has a yellow lemon-like colour. The melting point of sulfur is 388.36 K ?(115.21 °C, ?239.38 °F) and the boiling point is 717.8 K ?(444.6 °C, ?832.3 °F).
There are some 30 solid allotropes of sulfur. It has 23 isotopes, 4 of them are stable and naturally occurring isotopes the remaining are radioisotopes. These four stable isotopes are Sulfur-36 (0.01%±0.01%), Sulfur-34 (4.25%±0.24%), Sulfur-33 (0.75%±0.02%) and Sulfur-32 (94.99%±0.26%).
Sulfur is known to Chinese and other civilizations as a compound since 2000 BCE. As an element, it was recognized by French chemist Antoine Lavoisier in 1777.