Solved UPSC CDS/OTA Question
A solved UPSC CDS/OTA PYQ — decoded step-by-step.
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Q · Chemical EquationsMedium · 45s
Which of these reactions is correctly balanced?
TopicChemical Equations
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained — no skipped algebra.
B is balanced; A, C, and D are unbalanced.
Final Answer: Option B — Zn + 2HCl → ZnCl₂ + H₂