How many electrons would you expect to find around an atom of scandium?

Scandium Z = 21 has an electronic configuration of 1s²2s²2p⁶3s²3p⁶3d¹4s².

This shows that Scandium has 21 electrons with three outermost or valency electrons. It is a d-block elements whose valence electrons are equal to their group number, which is equal to the number of electrons in the valence shell.