HOBr     +
  NaOH
              Â
-------->Â Â Â Â Â Â Â NaOBr
+Â Â Â Â Â H2O
        Â
1.27Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â
0.43
        1.27
-0.43Â Â Â Â Â Â Â Â Â 0.43
-0.43 =0
        =
0.84Â Â Â Â Â Â Â Â Â Â
  0.43 0
Its a buffer solution , acidic buffer
So
pH = pka + log(salt/acid)
   = -log(2.5x10-9 ) + log (
0.43/0.84)
  = 8.6 + (-0.29) = 8.3
b) its a also an acidic buffer solution
pH = pka + log(salt/acid)
   = -log(2.5x10-9 ) + log (
0.67/0.98)
   = 8.6 +  (-0.16)
       = 8.43
