矽(silicon)
非金属到半金属化学元素，化学符号Si，原子序数14。在地壳中的丰度仅次於氧，居第二位。它从不以游离状态存在，但在几乎所有的岩石以及砂、黏土和土壤中，都存在矽的化合物︰或者与氧化合成二氧化矽（SiO2），或者与氧和金属形成矽酸盐矿物。在很多植物中和某些动物中，也都含有矽的化合物。纯矽是一种质硬的深灰色固体，具有金属光泽，其晶体结构和金刚石相同。矽是一种非常重要的半导体；掺入（参阅dopant）硼、磷或砷後，可用於各种电子电路和开关器件，包括电脑晶片、电晶体和二极体。在冶金学上，矽也可用作还原剂（参阅reduction），并用於钢铁、黄铜和青铜中。在化合物中矽通常为4价。作为砂和黏土的二氧化矽有许多用途；作为石英，可以加热而形成特种玻璃。矽酸盐用於制造玻璃、搪瓷和陶瓷；矽酸钠（水玻璃）用於肥皂、木材处理、水泥和染料。亦请参阅silane、silicone。
English version：
silicon
Nonmetallic to semimetallic chemical element, chemical symbol Si, atomic number 14. Second only to oxygen in abundance in the earth's crust, it never occurs free but is found in almost all rocks and in sand, clay, and soils, combined with oxygen as silica (silicon dioxide, SiO2) or with oxygen and metals as silicate minerals. It occurs in many plants and some animals. Pure silicon is a hard, dark gray solid with a metallic luster and the same crystal structure as diamond. It is an extremely important semiconductor; doped (see dopant) with boron, phosphorus, or arsenic, it is used in various electronic circuit and switching devices, including computer chips, transistors, and diodes. Silicon is also used in metallurgy as a reducing (see reduction) agent and in steel, brass, and bronze. Its usual valence in compounds is 4. Silica is used as sand and clay for many purposes; as quartz, it may be heated to form special glasses. Silicates are used in making glass, enamels, and ceramics; sodium silicates (water glass) are used in soaps, wood treatment, cements, and dyeing. See also silane, silicone.