Leaving Certification (LC) Chemistry Practice Exam

The dissociation of an Arrhenius acid involves the release of hydrogen ions (H⁺) into solution. This process is essential to the definition of Arrhenius acids, which are substances that produce hydrogen ions when dissolved in water.

In the correct representation, HA acts as the Arrhenius acid. When it dissociates, it breaks apart to produce H⁺ ions and the corresponding conjugate base A⁻. This reaction accurately reflects the behavior of an Arrhenius acid in an aqueous environment, confirming the release of protons that contributes to the acidic properties of the solution.

Understanding why other options do not represent the dissociation of an Arrhenius acid further clarifies this concept. The second option describes a situation where HA combines with an existing hydrogen ion to form a different species, which does not demonstrate dissociation. The third and fourth options involve the formation of hydroxide ions (OH⁻), indicating they are related to the behavior of bases rather than acids. Thus, they cannot accurately depict the dissociation of an Arrhenius acid.