In solution, hydronium ions ([tex] H_{3}O^{+} [/tex]) are acidic, because they readily donate their protons to try and maintain their neutral state, the well-known molecule, [tex] H_{2}O [/tex], or water.
On the other hand, hydroxide ions, ([tex] OH^{-} [/tex]) are basic, because they want to accept a proton to become neutral, again in the form of water. This means that they want these protons, thus depleting the solution of protons, making the solution more basic.
Therefore, an acid solution contains more hydronium ions than hydroxide ions.
