Sulfur dioxide is a common, heavy, colorless gas with a distinct odor. Its chemical formula is SO2; its extended formula is O2S. Since sulfate is in the chalcogen group, sulfur dioxide has a pungent odor similar to flatulence. A typical property of the compound includes being highly acidic. When dissolved in water, sulfur dioxide transforms into sulfuric acid, an intermediate substance whose properties increase the oxidation and deterioration process. Hence, this compound is found in some processed foods, particularly dried fruit, to extend the shelf-life of these products. Since sulfur dioxide is an oxidant, when consumed often, it can become carcinogenic and cause potentially fatal illnesses like chronic bronchitis and asthma. Sulfur dioxide is also regularly used in fabrics. Many clothes companies use sulfur dioxide to process cotton because it is inexpensive and easily found. Overall, sulfur dioxide is a unique substance with numerous properties.