Why is an atom of an element belonging to the alkali Metal family highly reactive because it has only one outer shell electron eight outer shell electrons

An atom of an element belonging to the alkali metal family is highly reactive because it has only one outer shell electron. Atoms are most stable when their outermost energy level is filled with electrons. In the case of alkali metals, they have only one electron in their outermost energy level, making them highly reactive as they readily lose this electron to achieve a full outer shell with eight electrons. This loss of electrons allows them to form positively charged ions, which can easily bond with other elements to form compounds.