Question

Riya performs two set of experiments to study the length of the foam formed which are as follows: 

Set I: She takes 10 mL of distilled water in test tube ‘A’ and adds 5-6 drops of liquid soap in it and shakes the test tube vigorously. 

Set II: She takes 10 mL of distilled water in a test tube ‘A’ and adds 5-6 drops of liquid soap with half spoonful of CaSO₄ in it and shakes the test tube. Write your observation and reason.

Answer 1

Set I will have more length of foam because it consists of soft water. 

Set II will form less foam because it consists of hard water due to the presence of CaSO₄.