Which statement correctly defines an Arrhenius acid?

Which statement correctly defines an Arrhenius acid?

• A. An Arrhenius acid dissociates in water to produce H+.
• B. An Arrhenius acid dissociates to produce OH-.
• C. An Arrhenius base dissociates to produce H+.
• D. An Arrhenius base increases the pH by absorbing H+.

Answer: (A)

In the Arrhenius view, acids are substances that dissociate in water to increase the concentration of H+ (hydronium) ions in solution. The statement that an Arrhenius acid dissociates in water to produce H+ fits this idea perfectly, since adding H+ raises the acidity of the solution. In water, that H+ is actually present as H3O+, but H+ is the common shorthand used in this context. The other ideas mix up acid and base roles or describe products that aren’t produced by acids in aqueous solution. Producing OH− is the hallmark of a base, not an acid. Claiming that a base dissociates to produce H+ contradicts the Arrhenius definitions. And saying a base increases pH by absorbing H+ glosses over the standard mechanism, which centers on generating hydroxide ions that raise pH rather than simply removing H+ by absorption.

In the Arrhenius view, acids are substances that dissociate in water to increase the concentration of H+ (hydronium) ions in solution. The statement that an Arrhenius acid dissociates in water to produce H+ fits this idea perfectly, since adding H+ raises the acidity of the solution. In water, that H+ is actually present as H3O+, but H+ is the common shorthand used in this context.

The other ideas mix up acid and base roles or describe products that aren’t produced by acids in aqueous solution. Producing OH− is the hallmark of a base, not an acid. Claiming that a base dissociates to produce H+ contradicts the Arrhenius definitions. And saying a base increases pH by absorbing H+ glosses over the standard mechanism, which centers on generating hydroxide ions that raise pH rather than simply removing H+ by absorption.