This document discusses the scandium group of elements, including scandium, yttrium, lutetium, and lawrencium. It provides details on their electron configurations, periodic table placement, chemical and physical properties, and extraction methods. The key points are:
1) The elements show trends in their outer electron configurations but lutetium is an exception due to relativistic effects.
2) They are reactive metals that are usually oxidized to the +3 oxidation state, forming stable oxides with high melting points.
3) Their oxides and compounds form when reacted with acids or halogens. Extraction of the pure metals is difficult due to their high melting points.