(3) loses one electron and becomes positively charged
Lithium has one valence electron and Bromine has seven. Therefore Lithium will give up its one to Bromine for both to have an octet
They all have something to do with electricity
So the equation is balanced, meaning they have the smallest amounts of each element in the reactants to create the products.
So, 2 moles of H2S (the coefficient) contributes to 2 moles Ag2S, which is why the ratio is 2:2.
I hope that made sense.
