Indicators change color when an acid and a base are mixed together. The change in color most likely indicates that a chemical change has occured. a physical change has occured. a new acid has been produced. a new base has been produced.
a physical change is mostly identified even without indicators i.e candle wax about forming a new acid or base I guess we have to include a ph scale to ascertain since the salt can be acidic but not necessarily an acid
