Solved UPSC CDS/OTA Question
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Q · Soap and DetergentsMedium · 45s
Which of the following statements is true regarding detergents?
TopicSoap and Detergents
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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Detergents do not form scum with Ca²⁺/Mg²⁺, so they remain effective in hard water.
Final Answer: Option B — Detergents work well in both soft and hard water.