At what pH will a 10−4M solution of an indicator with Kb=1×10−11change colour?

At what pH will a 10−4M solution of an indicator with Kb=1×10−

1.	At what pH will a 10−4M solution of an indicator with Kb=1×10−11change colour?
Answer» Solution :INDICATOR changes COLOUR when `PH =pKI_n , pH = 14 -11 =3`