like using a electron dot diagram what are the most common ions formed for Lithium-LiAlAluminumPhosphors and Br bromine
To find the mass number, you need the total number of protons AND neutrons.
To answer this question make sure you have your periodic table handyAtoms generally want to have a full outer electron shell, so to use your example of Lithium, Li, this is in group 1 of the periodic table, meaning that is has 1 electron in the outer shellTherefore for lithium to get a complete outer shell it will either need to gain 7 electron, or lose 1, which is what happens, Lithium will lose 1 electron, hence it will become Li1+ If we went to the other end, e.gBromine which is in group 7, this means it has 7 electrons in the outer electron shellUsing the theory that atoms want a full outer shell it will either lose 7 electron, or gain 1, which again this is what happensBromine GAINS 1 electron, giving it a -1 chargetherefore it becomes Br 1-If a atom is in group 2, then it will lose two electrons, giving it a 2- charge and the reverse is also trueJust remember check what group it is in on the periodic table, think which outcome is more likely(Atoms like to get to a full outer shell), and if it gains electrons, then it will gain a minus charge, if it loses electrons it become positive.
