Solved UPSC CDS/OTA Question
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Q · Soap and DetergentsMedium · 45s
Which of the following is responsible for the cleansing action of soap?
TopicSoap and Detergents
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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Soap molecules form micelles. The hydrophobic tail attaches to grease; the hydrophilic head remains in water, allowing emulsification.
Final Answer: Option A — The hydrophobic tail binds with dirt and grease, while the hydrophilic head binds with water.