If an atom has only 1 electron in its outermost shell, how will it behave?

An atom with only 1 electron in its outermost shell is typically very eager to lose that electron in order to achieve a more stable electron configuration. This behavior is characteristic of metals, especially alkali metals like lithium or sodium, which have a single electron in their outermost shell. When an atom loses this outer electron, it can easily conduct electricity because the remaining positively charged nucleus can attract more electrons from neighboring atoms and create a flow of electric current.

In conducting materials, the presence of free electrons greatly facilitates the movement of electric charge. The single outer electron can move freely through a lattice structure of metal atoms, allowing for this conduction of electricity. Thus, such an atom will indeed behave as a good conductor owing to its ability to readily give up the outer electron and allow for the flow of electrons throughout the material.