Solved UPSC CDS/OTA Question
A solved UPSC CDS/OTA PYQ — decoded step-by-step.
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Q · Atoms and MoleculesMedium · 45s
Which of these follows the law of constant proportions?
TopicAtoms and Molecules
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.
A compound always has elements in a fixed ratio by mass.
Final Answer: Option D — All of the above