Question

when few drops of phenolphthalein are added to dilute solution of sodium hydroxide a pink colour is produce . what will be the colour of final mixture when excess of Hcl is added to it

Answer 1

the nature of resulting solution will be acidic hence it will be colourless as phenolphthalein is colourless in acidic medium.

The sodium hydroxide is neutralized by HCl making Common salt which is neutral ... the excess acid present makes the solution acidic.

Answer 2

Answer:

When few drops of phenolphthalein are added to dilute a dilute solution of sodium hydroxide a pink colour. The colour of dilute solution of Sodium hydroxide turns pink or adding Phenolphthalein as  NaOH is a base .When excess of HCl is added the final mixture becomes colourless due to  neutralisation of base with an acid.