Here is a site my buddie has to help you. Well co-owner..
https://www.quora.com/Why-is-fresly-prepared-FeSO4-required-for-the-ring-test
No, but we can make it conduct energy by adding salt
If the energy level of a certain element is filled based on the maximum number of allowable electrons per level, then it is no longer reactive. With this, half-filled energy level means that the element may retain those electrons and attract electrons from other elements or it may give off its electrons.