# What is the net ionic reaction for the acid-base reaction of "HCl" with "NaNO"_3?

May 14, 2016

There is no acid-base reaction.

#### Explanation:

It takes two to tango: an acid-base reaction needs both an acid and a base. $\text{HCl}$ is fine for an acid, but ${\text{NaNO}}_{3}$ isn't a base (at least under ordinary conditions). So, no reaction.

May 14, 2016

Given that sodium is more active than hydrogen in the activity series, this reaction doesn't really occur.

The reaction would have been:

$\textcolor{b l u e}{{\text{HCl" + "NaNO"_3 rightleftharpoons "NaCl" + "HNO}}_{3}}$

Decomposing this into a "pseudo-ionic equation", we would have gotten:

stackrel("Bronsted acid")overbrace("HCl") + stackrel("Bronsted Base")overbrace("NO"_3^(-)) rightleftharpoons stackrel("Conjugate base")overbrace("Cl"^(-)) + stackrel("Conjugate acid")overbrace("HNO"_3)

with ${\text{Na}}^{+}$ as one of the "spectator" counterions.

The pKa of $\text{HCl}$ is about $- 7$, but the pKa of ${\text{HNO}}_{3}$ is about $- 1.3$. This says that $\text{HCl}$ is a stronger acid than ${\text{HNO}}_{3}$, and thus the equilibrium would have lied on the side of ${\text{HNO}}_{3}$, the weaker acid.

Fully decomposing it would give:

$\textcolor{red}{\cancel{{\text{Cl"^(-) + "NO"_3^(-)) rightleftharpoons cancel("Cl"^(-) + "NO}}_{3}^{-}}}$

in which nothing really happened, and ${\text{H}}^{+}$ is the other "spectator" counterion.

Given that sodium is more active than hydrogen in the activity series, this reaction doesn't really occur.