The majority of bases are composed of minerals which react with acids (by accepting H+ ions) to produce salts and water. This gives bases the capability to neutralize acids. According to the Brondsted-Lowry model, the definition of a base is any ion or molecule which can accept a proton. Bases typically contain elements such as nitrogen, oxygen, as well as other elements. They often are composed of hydroxide ions, which are able to accept protons via covalent bonds.