The group 13 of the periodic table consists of the elements Boron, aluminium, gallium indium, thallium and the newly discovered elements ununtrium(uut). Occurrence Boron occurs in two forms . Its abundance in the earth's crust is very low. Boron mainly occur as: 1) Orthoboric acid, H3BO3 2)Borax, Na2[B4O5(OH)4].8H2O or Na2B4O7.10H2O 3)kernite, Na2[B4O5(OH)4] … [Read more...] about Physical Properties Of Boron Family