Home › CBSE Class 9 › chemistry › atomicfoundations › In Lavoisier's experiments, why was it crucial t…
In Lavoisier's experiments, why was it crucial to perform reactions in SEALED containers?
ATo prevent any gases produced or consumed from escaping (or air from entering) — so that all matter is accounted for in the mass measurement
BTo prevent loss of heat
CSealed containers look more scientific
DSealed containers conduct electricity
Answer & Solution
Correct answer: A. To prevent any gases produced or consumed from escaping (or air from entering) — so that all matter is accounted for in the mass measurement
Many chemical reactions involve gases (combustion produces CO₂; rusting consumes oxygen). If gas escapes (or enters), measured mass changes — falsely appearing to violate conservation. Lavoisier was the first to use carefully sealed apparatus, definitively proving that total mass is conserved when all reactants and products (including gases) are accounted for.