How do we address mass and charge in a #"single displacement reaction"#?
You account for them.....
All chemical equations are balanced with respect to (i) mass, and (ii) charge....
And so in a
And so for an actual reaction, CHARGE is conserved......neutral reactants give neutral products......and charged reactants give products of equal charge........
In the given reaction, which of course is a redox reaction, of course the cations are present as the counterions of some anion that gives soluble salts, but this is the province of experiment.
And so charge is conserved as well as mass. Is it conserved in the iron/copper couple?
Note that when I say
So if you credit one account, you must DEBIT another. At the end of the day when an accountant (so-calls) reconciles his/her account, if the debits DO NOT MATCH the credits precisely, SOMEONE, the client or the bank, is out of pocket.
Chemistry follows the same principle, which of course is the principle of stoichiometry,