Solved UPSC CDS/OTA Question
A solved UPSC CDS/OTA PYQ — decoded step-by-step.
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Q · Chemical EquationsMedium · 45s
Select the reaction representing precipitation:
TopicChemical Equations
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
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BaSO₄ precipitates out in a double displacement reaction.
Final Answer: Option C — BaCl₂ + Na₂SO₄ → BaSO₄ ↓ + 2NaCl