硫(sulfur)
非金属化学元素，化学符号S，原子序数16。硫元素非常活泼，但可以以天然硫的形式存在，也以化合物的形式构成各种矿石（如黄铁矿、方铅矿、辰砂）、煤炭、石油和天然气都含数量不等的硫化合物；有的矿泉水也含硫。硫是矿物的最丰富的组分之一，仅次於氧和矽居第三位。同时也是四种最重要的基本化学商品之一。纯硫是无味无嗅的淡黄色脆性固体，呈晶体状或非晶体状，如硫黄石和硫华。它能与几乎所有其他元素化合，原子价为2、4或6。最常见的一种化合物是硫化氢，是一种具有臭鸡蛋气味的极毒气体。除了金和铂以外，所有的金属都能跟硫化合生成硫化物，许多矿物就是这种硫化物。硫的氧化物有二氧化硫和三氧化硫，溶於水中时分别形成亚硫酸和硫酸。硫与卤素的几种化合物在工业上有重要用途。亚硫酸钠可在纸浆生产和摄影术中用作还原剂。硫的有机化合物包括数种含硫氨基酸、磺胺药以及多种除虫剂、溶剂，以及用於制造橡胶和合成纤维等的许多原料。
English version：
sulfur
Nonmetallic chemical element, chemical symbol S, atomic number 16. It is very reactive but occurs native in deposits, as well as combined in various ores (e.g., pyrite, galena, cinnabar); in coal, petroleum, and natural gas; and in the water in sulfur springs. Sulfur is the third most abundant constituent of minerals and one of the four most important basic chemical commodities. Pure sulfur, a tasteless, odorless, brittle yellow solid, occurs in several crystalline and amorphous allotropes, including brimstone and flowers of sulfur. It combines, with valence 2, 4, or 6, with nearly all other elements. Its most familiar compound is hydrogen sulfide, the poisonous gas that smells like rotten eggs. All metals except gold and platinum form sulfides, and many ores are sulfides. The oxides are sulfur dioxide and sulfur trioxide, which when dissolved in water make sulfurous acid and sulfuric acid, respectively. Several sulfur compounds with halogens are industrially important. Sodium sulfite (Na2SO3) is a reducing agent used to pulp paper and in photography. Organic compounds with sulfur include several amino acids, the sulfa drugs, and many insecticides, solvents, and substances used in making rubber and rayon.