Question

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

Answer 1

There is no acid-base reaction.

Explanation:

It takes two to tango: an acid-base reaction needs both an acid and a base. `"HCl"` is fine for an acid, but `"NaNO"_3` isn't a base (at least under ordinary conditions). So, no reaction.

Answer 2

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

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The reaction would have been:

`color(blue)("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 `"Na"^(+)` as one of the "spectator" counterions.

The pKa of `"HCl"` is about `-7`, but the pKa of `"HNO"_3` is about `-1.3`. This says that `"HCl"` is a stronger acid than `"HNO"_3`, and thus the equilibrium would have lied on the side of `"HNO"_3`, the weaker acid.

Fully decomposing it would give:

`color(red)(cancel("Cl"^(-) + "NO"_3^(-)) rightleftharpoons cancel("Cl"^(-) + "NO"_3^(-)))`

in which nothing really happened, and `"H"^(+)` is the other "spectator" counterion.

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