Boron, aluminum, gallium, and indium lose three valence electrons to from ions with a 3+ charge. Thallium only loses one valance electron and forms ions with a 1+ charge. Gallium and indium can also form ions with a 1+ charge. The elements in group 4A are carbon (metal), silicon (metalloid), germanium (metalloid), tin (metal), and lead (metal). Because there is such a wide range of properties there are not many rules that apply to all of the elements in group 4A. Nitrogen, phosphorus, arsenic, antimony, and bismuth are all the elements in group 5A. Nitrogen and phosphorus are non metals, arsenic and antimony are metalloids, and bismuth is a metal. They each have five valance electrons and display a wide variety of physical and chemical properties. The elements in group 6A are oxygen (nonmetals), sulfur (nonmetals), selenium (metalloids), tellurium (metalloids), and polonium. Polonium is the most metallic member of group 6A. These elements have valance electrons and act mainly as nonmetals. They usually gain two electrons to form ions with a 2- charge. Fluorine, chlorine, bromine, iodine, and astatine can from compounds with almost all metals and belong to the group 7A. They are called halogens. There are gasses, liquids, and solids in group 7A. Aside from astatine, which is a radioactive element with no known uses, the other elements are reactive nonmetals that are always combined with other elements in nature. They form ions with a 1- charge. Helium, Neon, Argon, Krypton, Xenon, and Radon are all the elements in group 8A. They are all noble gases that are colorless and unreactive. They are known primarily for their stability. Noble gases have the maximum number of electrons in their outermost energy levels, eight. Helium is the only one with two. They very rarely react because of their stability. Helium, neon, and argon have no known compounds.
D-Block Elements.
The d-block elements are called transition metals.