Predict the products of the following acid–base reactions, and predict whether the equilibrium lies to the left or to the right of the reaction arrow:
(a) O^2-(aq) + H₂O(l) ⇌
(b) CH₃COOH(aq) + HS^-(aq) ⇌
(c) NO₂^-(aq) + H₂O(l) ⇌

Acid-base reactions involve the transfer of protons (H+) between reactants. In this context, an acid donates a proton, while a base accepts it. Understanding the roles of acids and bases is crucial for predicting the products of the reaction and determining the direction of equilibrium.

The position of equilibrium in a chemical reaction indicates the relative concentrations of reactants and products at equilibrium. If the equilibrium lies to the right, products are favored; if to the left, reactants are favored. Factors such as concentration, temperature, and the nature of the reactants influence this position.

Water is often referred to as the 'universal solvent' due to its ability to dissolve many substances, including acids and bases. In acid-base reactions, water can act as a medium for proton transfer, and its role in the reaction can affect the strength of the acids and bases involved, influencing the overall reaction dynamics.