* Boron hydrides, the simplest boron compounds, contain hydrogen atoms bonded to boron. Many boron hydrides are also called boranes. Diborane (B2H6) and tetraborane (B4H10) are two common boranes.

* Boron halides contain three halide atoms (fluorine, chlorine, bromine, or iodine) bonded to one boron atom. For example, boron trifluoride (BF3) is a colorless gas that reacts vigorously with water.

* Boron oxides (diboron trioxide, B2O3) and boron nitride (BN) have more than one boron atom bonded together. Both boron oxide and boron nitride are white solids.

Boron-Oxygen-Hydrogen Compounds

* Borates, such as sodium borate (borax, Na2B4O7-10H2O) and potassium borate, are salts derived from boric acid (H3BO3). Borates are used in the production of certain types of glass, soaps, and cosmetics.

* Boric acid, a weak acid, is used in the preservation of wood, as an antiseptic, and in the production of other boron compounds.

Other Boron Compounds

Boron also forms a number of compounds with carbon. These compounds are known as organoboron compounds. They are used in the synthesis of organic materials, such as pharmaceuticals and dyes.

Boron forms both ionic and covalent compounds. In ionic compounds, boron acts as a metal, forming positive ions. In covalent compounds, boron acts as a nonmetal, sharing electrons with other atoms to form molecules.