Solved UPSC CDS/OTA Question
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Q · Chemistry in Daily LifeMedium · 45s
Which chemical is used for removing permanent hardness of water?
TopicChemistry in Daily Life
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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Washing soda (sodium carbonate) reacts with calcium and magnesium ions to remove permanent hardness.
Final Answer: Option C — Washing soda