Solved UPSC CDS/OTA Question
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Q · Chemical EquationsMedium · 45s
Which one of the following is an example of an unbalanced chemical equation?
TopicChemical Equations
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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Every step explained - no skipped algebra.
Fe + O₂ → Fe₂O₃ is unbalanced because the number of Fe and O atoms are not equal on both sides. All others are balanced.
Final Answer: Option C - Fe + O₂ → Fe₂O₃