Give the electronic configuration (electron arrangement) for these ions:
(as an example, an atom of sodium has 11 electrons and so it would be 2,8,1 . The Na+ ion must have one less electron since the ion is one-positive. Consequently, the electronic configuration is 2,8,0)
K+ (atomic number = 19)
F- (atomic number = 9)
O2- (atomic number = 8)