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?
Answers were Sorted based on User's Feedback
Answer / 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 |
Answer / arti naik
The pink colour appears due to the change in the structure
of the phenolphthalein indicator and it forms a disodium
salt due to the base NaOH which then gives it a pink colour.
Is This Answer Correct ? | 7 Yes | 3 No |
Answer / umesh patel
in basic media(in NaoH), phenolphthelin shows pink color
only
colorless if pH of the media goes below 8
pink color will appear if pH goes beyond the pH of 10.00
Is This Answer Correct ? | 11 Yes | 8 No |
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