Atoms and Molecules · UPSC CDS/OTA · Question 11 of 30

Atoms and Molecules – Question 11

Step-by-step solution. Atoms and Molecules for UPSC CDS/OTA.

Topic
Atoms and Molecules
Subject
General Studies
Difficulty
Medium
Solve Time
45–60 sec

Solved UPSC CDS/OTA Question

A solved UPSC CDS/OTA PYQ — decoded step-by-step.

Solve it the standard way once — then learn the shortcut.

Q · Atoms and MoleculesMedium · 45s

In chemical reactions, the law of conservation of mass was given by:

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.

Lavoisier established that mass is conserved in chemical changes.

Final Answer: Option B — Lavoisier
Solve Question✦ Build Plan
Atoms and Molecules Question 11 – UPSC CDS/OTA