# Calculate [OH-] ions in a 0.125 M solution of nitrous acid. Is this solution acidic or basic; how do you know? Make sure you include the ionization equation.

Mar 23, 2017

$\text{Nitrous acid}$, $H N {O}_{2}$, is a weak Bronsted acid, and ionizes in solution according to:
$H N {O}_{2} \left(a q\right) + {H}_{2} O \left(l\right) r i g h t \le f t h a r p \infty n s {H}_{3} {O}^{+} + N {O}_{2}^{-}$
It will give a weakly acidic solution. We could calculate ${H}_{3} {O}^{+}$, and $N {O}_{2}^{-}$, and $\left[H {O}^{-}\right]$ if we were given ${K}_{a}$ for this weak acid. Of course, I could look it up, but then so could you.