A good example of equilibrium would be the mixing of oil and water in a closed container.
Chemical equilibrium is a condition in which the concentrations of components of a chemical reaction remain unchanged and have no tendency to change.
Of all the options, the only one where the concentrations of the component reactants cannot change is a mixture containing oil and water in a closed container.
Oil and water are immiscible and thus, their concentrations remain constant.
More on chemical equilibrium can be found here: https://brainly.com/question/4289021
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