Question

Is ${H^ + }$ an acid or base?

Answer 1

Whether a solution is acidic or basic is determined by its ability to donate a ${H^ + }$ ion or a $O{H^ - }$ ion. If $O{H^ - }$ is dissociated in the solution then it is basic in nature, if ${H^ + }$ is dissociated by the solution, then it is acid in nature.

Complete answer:
The ${H^ + }$ ion cannot exist floating around the aqueous solution in this state. So in the aqueous solution the ${H^ + }$ ions are always associated with the lone pair of the water molecules and thus they together form ${H_3}{O^ + }$ . According to the Bronsted-lowry acid definition a substance which donates a proton or ${H^ + }$ ion to the other compound is known as acid. In the above reaction of ${H^ + }$ with the water it donates itself to the water in the reaction. Now according to Lewis acid, if a substance accepts a pair of electrons to form a covalent bond, is known as acid. Here again it accepts the electrons in its empty orbital. So going by these two definitions ${H^ + }$ is an acid.
Also one must know that the all acids are limited by the strength of ${H_3}{O^ + }$ when dissolved in the water. This ${H^ + }$ ion is therefore an acid as it generates ${H_3}{O^ + }$ .
Therefore a naked ${H^ + }$ associated with the molecule is an acid as the ${H^ + }$ cannot exist freely floating in the water.

Note:
${H_3}{O^ + }$ is the common name for the aqueous cation ${H_3}{O^ + }$ , the type of oxonium ion produced by protonation of water. It is the positive ion present when an Arrhenius acid is dissolved in water, as Arrhenius acid molecules in solution give up a proton to the surrounding water molecules.