If a new element were discovered and it was found to form #1^-#ions, in which group you place itin the periodic table?
Group VII A or the halogens
The halogens typically form ions with a -1 charge.
The valence structure of the VII A elements is
These elements are short one electron of achieving the stable electron structure
Because of the need for one more electron in order to become stable, the VII elements have the highest electronegativitity of the elements in the same period. This causes the family of elements to commonly have a negative one charge.
If the VII elements combine with an element like oxygen that has a higher electronegativity than the halogen, these elements can also have oxidation numbers of +1, +3, +5 and +7.