Which equation is used to describe the dissociation of a strong acid in water?

The equation that describes the dissociation of a strong acid in water is written as HA → H⁺ + A⁻. This notation indicates that a strong acid, represented by HA, dissociates completely in water to yield hydrogen ions (H⁺) and conjugate base ions (A⁻).

The key point in understanding this is that strong acids are characterized by their ability to ionize completely in aqueous solution, which means that nearly all molecules of the acid dissociate to form ions. The use of the arrow (→) instead of a double arrow (⇌) signifies that the reaction goes to completion and does not establish an equilibrium, consistent with the behavior of strong acids.

This clarity in representation reflects how, once a strong acid is added to water, it produces a high concentration of H⁺ ions, resulting in a lower pH of the solution. By contrast, other options involving reversible reactions or the addition of hydroxide ions do not accurately depict the complete dissociation characteristic of strong acids.