Using the periodic table, how would you predict the charges of the ions of the following elements?
The question is very compless. Ga and Sr are two metals; they have in the last energetic level a number of electrons given from the number of the column of periodic table in which they lay;
then Sr has two electrons that can lose and becomes
Br an Se are non metals and they try to purchase electrons to complete their octet, becoming anions. Br in the seventh column A (or XVII) has 7 electrons and becomes
They can also form anions bonding themselves with oxygen
Se, with oxygen can also forms
As is an anphoteric element and can give thre of its 5 electrons as metal (As^3+) or can form anions with oxigen
I hope to have helped you sufficiently