what is the difference between a redox rxn in and acidic soln or basic

Answer 1

In acid solution the balance is made with H^+ and H2O. In basic solution the balance is made with OH^- and H2O. However, none of this makes much difference since there are several schemes that work and this is just a form to follow to balance those tough redox equations. One method is to always balance with H^+ and H2O, then add OH^- to that if it is a basic solution.