But I tend to think that for a given old bottle of the acid, the oxidation potential of the solution is variable and unknown.

"The measure of a material to oxidize or lose electrons is known as its oxidation potential".

The table below shows a few reduction potentials that could easily be changed to oxidation potential by simply reversing the sign.

To tell which is the strongest reducing agent, one can change the sign of its respective reduction potential to make it oxidation potential.

Corrosion occurs whenever there's a difference in oxidation potential.

Ozone has a very high oxidation potential.

In general, one cannot simply relate oxidation potential to reactivity.

Here they are arranged in order of their oxidation potential:

The oxidation potential for a particular electrode is just the negative of the reduction potential.

The oxidation potential of copper may be responsible for some of its toxicity in excess ingestion cases.