alleryStart learning →In a chemical equilibrium, what is true of the forward and the reverse reaction?
AThey run at equal rates, so amounts hold steady
BThey both stop once the amounts hold steady
CThey run at rates in a fixed two to one ratio
DThey take turns, only one running at a time
Answer & Solution
Correct answer: A. They run at equal rates, so amounts hold steady
1. At equilibrium the forward reaction and the reverse reaction proceed at the same rate.
2. Because the two rates match, the concentrations of reactants and products no longer change.
3. Neither reaction stops, so equilibrium is a dynamic balance rather than a halt.
4. Rates locked in any ratio other than one to one would leave the concentrations drifting.
_Source: OpenStax Chemistry (CC BY 4.0), Ch 13 "Fundamental Equilibrium Concepts", section 13.1 Chemical Equilibria_
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