Environment & Ecology question from JKAS Prelims, 2023 by JKPSC
Litmus solution is a purple dye extracted from:
1. Hibiscus
2. Lichen
3. Lotus
4. Lily
Last updated Jun 24, 2026
Correct Answer:
Option B —
2 only
Litmus is a water-soluble mixture of different dyes extracted from Lichens (specifically species like Roccella tinctoria). In its neutral state, the solution is purple. It is the most commonly used natural indicator in laboratories to test for acidity or alkalinity. Key Concepts of Litmus
Source: It is obtained from Lichens, which are symbiotic organisms consisting of a fungus and an alga.
Function: It acts as a pH indicator.
Acidic medium: Turns blue litmus Red.
Basic (Alkaline) medium: Turns red litmus Blue.
Neutral medium: Remains Purple.
Other Natural Indicators
Since this is a common topic for exams like the UPSD or other civil services, it is helpful to know other natural indicators often tested:
Turmeric: Remains yellow in acid, turns reddish-brown in base.
China Rose (Hibiscus): Turns dark pink (magenta) in acid and green in base.
Red Cabbage: Turns red in acid and green/yellow in base.
Answer verified by Quintessence Classes faculty — Karan Nagar, Srinagar.
