# Comment on the electrical neutrality of strong acids. What is the equilibrium that defines the strength of an acid?

Jan 22, 2017

All bulk materials are electrically neutral............

#### Explanation:

The parent acids, $H X$, $H N {O}_{3}$, $H C l {O}_{4}$, ${H}_{2} S {O}_{4}$, $H O A c$............are all neutral entities. Of course in aqueous solution (and most of them are supplied as aqueous solutions), the following equilibrium occurs:

$H X \left(a q\right) + {H}_{2} O \left(l\right) r i g h t \le f t h a r p \infty n s {H}_{3} {O}^{+} + {X}^{-}$

For stronger acids, the equilibrium lies to the RIGHT; for weaker acids the equilibrium lies to the LEFT as we face the page. The $\text{hydronium ion}$, ${H}_{3} {O}^{+}$, is conceived to be the $\text{acidium species}$ in solution, a cluster of water molecules with an EXTRA ${H}^{+}$, i.e. ${H}_{7} {O}_{3}^{+}$, or ${H}_{9} {O}_{4}^{+}$; the extra ${H}^{+}$ moves, or tunnels if you like as does a ball in a rugby maul. We write ${H}^{+}$ or ${H}_{3} {O}^{+}$ for convenience. Of course, with this positively charged species, there is a correpsonding negatively charged species, an anion.

There are other solvent systems we could use, but water is clearly the most convenient.