Question

You are provided with four test tubes containing sugar solution, baking soda solution, tamarind solution, salt solution. Write down activity to find nature (acidic/basic/neutral) of each solution.

Answer 1

Acid-base Indicators

• Litmus paper is a type of paper that changes color when dipped in acidic solutions and can therefore be used to measure acidity.
• Under acidic conditions, blue litmus paper turns red, whereas red litmus paper turns blue under basic or alkaline conditions.
• Phenolphthalein is colorless by nature but becomes pink in alkaline solutions.
• Phenolphthalein is an acid-base indicator used to determine a solution's pH.

Test to find nature of each solution

• For the test tubes containing sugar solution, baking soda solution, tamarind solution, and salt solution, add blue litmus solution and then red litmus solution.
• The observations are as follows:

Solutions	Blue litmus	Red litmus	Nature
Sugar solution	Remains blue	Remains red	Neutral
Baking soda solution	Remains blue	Turns blue	Basic
Tamarind solution	Turns red	Remains red	Acidic
Salt solution	Remains blue	Remains red	Neutral