Arnav is provided with three kinds of liquid of them one is sodium hydroxide; another is hydrochloric acid and third is a sugar solution. How will he identify them when he has only turmeric indicator.

Turmeric is yellow in colour, when it is exposed to neutral (Sugar Solution) or acidic substances (Hydrochloric Acid) it will retain its yellow colour. However, if turmeric is exposed to more alkaline substances (sodium hydroxide) it becomes a dark pink/red. So first we detect sodium hydroxide -a basic substance by a colour change from yellow to dark or red. Then will test for an acid or neutral substance with indication of no colour change. Now out of these two, we will mix one with already tested solution for basic substance -sodium hydroxide with dark or red colour, if on mixing the colour reverses back to yellow, the liquid is an acid and the remaining third liquid is neutral.