Question

Turmeric is a natural indicator. On adding its paste to acid and base separately, which color is observed?
A. yellow in both acid and base
B. yellow in acid and red in the base
C. Pink in acid and yellow in the base
D. Red in acid and blue in the base.

Answer 1

Hint: Indicators are the chemical compounds which when added to the acidic solution or basic solution change its color with the variation of pH. Indicators are usually used in the titration process. Turmeric is a natural indicator that is acidic in nature.

Complete step by step answer:
The pH of the solution helps to measure the concentration of ${H^ + }$ ion. The acidic compounds have ${H^ + }$ ion and the basic compounds have $O{H^ - }$ ion. The concentration of the solution helps to know the strength of the acid or base. The compound whose pH is below 7 is termed as acids and above 7 is termed as bases.
Acid and bases react with each other to form a neutral salt with the elimination of water. This reaction is called a neutralization reaction.
The general neutralization reaction is shown below.
$Acid + base \to salt + water$
Turmeric is used as a natural indicator. It is added to the solution to determine its acidity and basicity. The turmeric is acidic in nature and it is yellow in color. When turmeric paste is added to the acidic solution, it remains unchanged. The color in the acidic solution is yellow. When turmeric paste is added to the basic solution the yellow color changes to red color due to the neutralization reaction.
Therefore, the correct option is B.


Note:
In the neutral solution, when turmeric paste is added, the yellow color of the turmeric remains the same as it is not an acidic solution nor a basic solution, so there will be no reaction.