Sulfur Dioxide
Sulfur Dioxide, a colorless, nonflammable gas that has a sharp, pungent odor. It is easily liquefied and is a good solvent for many organic compounds. Sulfur dioxide gas is used in the production of sulfuric acid, in the manufacture of pulp, and as a preservative for fruits and vegetables. The gas readily dissolves in water, with which it forms sulfurous acid, a bleaching and reducing agent. Sulfur dioxide is usually made by burning sulfur or roasting metallic sulfides such as iron pyrites.
In many industrial and residential areas, sulfur dioxide is a major air pollutant. It is released into the air by furnaces that burn sulfur-containing coal or oil. Even when present in only small amounts, sulfur dioxide irritates the respiratory tract. Prolonged exposure or higher concentrations can lead to chronic bronchitis, emphysema, and other diseases. Sulfur dioxide in the air can lead to the formation of acid rain.
Chemical formula: SO2.