Free Notes for Class 5–12 | CBSE | 24x7 Access
Student School Teacher Help
Home Schools Pricing
Log in Get Started
Class 10 Science Medium Mcq English Medium

In the classic NaOH-phenolphthalein-HCl activity, the pink colour disappears on adding HCl drop by drop because

Question
In the classic NaOH-phenolphthalein-HCl activity, the pink colour disappears on adding HCl drop by drop because
The medium becomes acidic
The medium becomes more basic
Water evaporates from the mixture
A precipitate forms
Answer
The medium becomes acidic
Detailed Explanation
As HCl neutralises the NaOH, the medium loses its basic character and phenolphthalein loses its pink colour.
Related Questions
Litmus, the natural indicator, is extracted from Science · Acids, Bases and Salts Turmeric, a natural indicator, turns which colour in the presence of a base Science · Acids, Bases and Salts Which of the following is a synthetic indicator Science · Acids, Bases and Salts Blue litmus paper turns which colour in an acid Science · Acids, Bases and Salts

Want the full Science question bank?

Log in for free to unlock practice tests, notes, and an AI tutor for Class 10.

Get started free