Answer to Question #157695 in Chemistry for Odalys

Question

Group 7a elements tend to lose or gain electrons when they form ions

Answer 1

The elements in the group 7a are called halogens. The outer shells of these elements, or the valence shells consist usually of five p electrons and two s electrons. Therefore, they need only one electron to complete the p electron energy level and become stable. Therefore, when they form ions, they usually gain one electron and have the charge of -1.