In acid base titration, after complet consumption of HCl by
NaOH, addition of next drop of NaOH will give pink colour
with phenolpthalein indicator. Why this pink colour appear?
Why not blue, black, green or anything elese?

Answer Posted / sarma dvv

Phenolpthalein indicator pH range = 8.2 To 10.0.
In this pH region only Phenolpthalein indicator shows pink
colour. below this pH it was colour less.

In acid base titration, Hcl neutralisation by NaOH,after
completion of neutralisation,affition of next drop of NAOH
the pH of the solution will be above 8.2. for this reason
it was showing pink colour

Is This Answer Correct ?    31 Yes 3 No



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