Solved UPSC CDS/OTA Question
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Q · Soap and DetergentsMedium · 45s
Which test can differentiate soap from a synthetic detergent?
TopicSoap and Detergents
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
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Soap loses effectiveness in hard water; detergents do not.
Final Answer: Option B — Hard water test