Consider a sample of water in a closed container. When the reaction H₂O(l) H₂O(g) Has reached equilibrium, what can we say about any specific water molecule? A)If it was present in the liquid it will always remain in the liquid. B)If it was present in the gas it will always remain in the gas. C)It will sometimes be in the liquid phase and sometimes in the gas phase. D)Both a and b are true.

Question

Quizplus · Accepted Answer

At equilibrium, the forward and reverse reactions are occurring at equal rates, therefore there is a dynamic exchange of water molecules between the liquid and gas phases. Any specific water molecule can be found in either phase at any given time. Therefore, choice A and B are incorrect as they suggest the molecule would only exist in one phase.

Consider a Sample of Water in a Closed Container