Solid creates hollow, branching rootlike structures called fulgurite via fusion. Organic chemistry studies the structure, properties, composition, reactions, and preparation by synthesis (or other means) of chemical compounds of carbon and hydrogen, which may contain any number of other elements such as nitrogen, oxygen and the halogens: fluorine, chlorine, bromine and iodine. Some organic compounds may also contain the elements phosphorus or sulfur. Examples of organic solids include wood, paraffin wax, naphthalene and a wide variety of polymers and plastics. Wood is a natural organic material consisting primarily of cellulose fibers embedded in a matrix of lignin. Regarding mechanical properties, the
Origin and use of the term metalloid their ability to form oxyanions. A common oxyanion of sulfur, for example, is the sulfate ion SO. Many metals can do the same. Chromium, for instance, can form the chromate ion CrO. Berzelius' terminology was widely adopted although it was subsequently regarded by some commentators as counterintuitive, misapplied, incorrect or invalid. In 1825, in a revised German edition of his "Textbook of Chemistry," Berzelius subdivided the metalloids into three classes. These were: constantly gaseous 'gazolyta' (hydrogen, nitrogen, oxygen); real metalloids (sulfur, phosphorus, carbon, boron, silicon); and salt-forming 'halogenia' (fluorine, chlorine, bromine, iodine). In 1844, Jackson gave the meaning of 'metalloid'