Question

Solid solution of sodium hydroxide a pink colour is produced what will be the colour of the final mixture when excess of hcl added to it

Answer 1

Phenolphthalein is a pH indicator, so the color of the solution depends on its pH. When the pH is _very_ low (<0), it is a bright orange, from 0 to slightly basic, it’s colorless and from 8.2 to very basic (>13) it’s the well known pink.

So, answering your question: dilute HCl will be acidic, but not overly, so initially, the solution will be colorless. By adding the NaOH a drop at a time, you will see a pink shade once you dropped it in, but mixing the solution will dispel that. This will go on for a while. When you reach the turning point (equal amount of base and acid), the solution becomes light pink and the color “stays” even after mixing. If you keep adding NaOH, the solution will become a strong, vibrant pink.

hope this may help you