In aqueous solution, Arrhenius acids increase the concentration of which ion?

In aqueous solution, Arrhenius acids increase the concentration of which ion?

• A. OH-
• B. H+
• C. Na+
• D. Cl-

Answer: (B)

Acids in water donate protons, which raises the concentration of hydrogen ions in solution. In aqueous solution, those protons are quickly solvated by water to form hydronium ions, so [H3O+] increases. That’s why the ion whose concentration goes up is hydrogen (as H+ or, effectively, H3O+). The other ions aren’t specifically produced by acid dissociation: OH- is associated with bases, and Na+ and Cl- are spectator ions that don’t reflect the defining action of an Arrhenius acid.

Acids in water donate protons, which raises the concentration of hydrogen ions in solution. In aqueous solution, those protons are quickly solvated by water to form hydronium ions, so [H3O+] increases. That’s why the ion whose concentration goes up is hydrogen (as H+ or, effectively, H3O+). The other ions aren’t specifically produced by acid dissociation: OH- is associated with bases, and Na+ and Cl- are spectator ions that don’t reflect the defining action of an Arrhenius acid.