Question

What is the `pH` of concentrated `HCl(aq)`?

Answer 1

Less than `-1`, but don't quote me.

Explanation:

`pH=-log_10([H_3O^+]).`

Thus `pH=-log_(10)(12)`, which value is less than `-1`.

The commercial reagent `37%` `m/m` is approx. `12" molar"`.