Correct Answer - Option 2 : pink
The correct answer is pink.
- An alkali is a water-soluble base.
- Bases have a soapy feel and they are bitter in taste.
- Phenolphthalein is an indicator to detect the presence of alkali or base in a solution.
- It changes its colour to pink in an alkaline solution.
- Phenolphthalein is colourless in acidic solutions.
So, the correct option is pink.
Some indicators and their colour change are given in the table below:
| Indicator |
Colour Change in Acidic Solution |
Colour Change in Basic or Alkaline Solution |
| Phenolphthalein |
Colourless |
Pink |
| Methyl Orange |
Red or Orange |
Yellow |
| Litmus Paper |
Red |
Blue |
| Turmeric |
Yellow |
Red |
| China Rose |
Dark pink |
Green |
