alleryStart learning →How can a system at equilibrium be temporarily pushed out of equilibrium?
ABy stirring the mixture more vigorously
BBy transferring it to a wider container
CBy labelling one reactant with an isotope
DBy adding or removing a reactant or product
Answer & Solution
Correct answer: D. By adding or removing a reactant or product
1. Equilibrium holds only while the reaction quotient equals the equilibrium constant.
2. Adding or removing a reactant or a product changes a concentration inside the quotient.
3. The quotient then no longer matches the constant, so the system is momentarily disturbed.
4. Further changes in all the concentrations follow until the quotient matches again.
_Source: OpenStax Chemistry (CC BY 4.0), Ch 13 "Fundamental Equilibrium Concepts", section 13.3 Shifting Equilibria: Le Châtelier's Principle_
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