[Bubblejerry]

I have an acidic solution that I can't identify. I added litmus to it to get an estimate of the pH and it came out dark red. It also has a density of 1 g/ml if that helps. Does anyone have any ideas on what it may be? As a backstory for it I took the sulfuric acid pads from a lead-acid battery and soaked them in water, the original solution was not acidic so I ran it through electrolysis with copper as an anode and lead oxide plates I got from the battery as a cathode. After doing this the solution came back as acidic. I boiled it down to about 15% it's original volume to try and concentrate it and the fumes that came off were white. But after doing this it came out with the given density and adding it to sugar failed to produce carbon. My best guess is that it is heavily diluted sulfuric acid, but the low density is discouraging.

[Borek]

I have an acidic solution that I can't identify. I added litmus to it to get an estimate of the pH and it came out dark red. It also has a density of 1 g/ml if that helps.

Zillions of solutions that could fit.

As a backstory for it I took the sulfuric acid pads from a lead-acid battery

That is a piece of information that definitely narrows down the problem.

electrolysis with copper as an anode

Is the solution blue? Was it bubbling?

My best guess is that it is heavily diluted sulfuric acid, but the low density is discouraging.

While I am not sure what was the exact chemistry taking place during the electrolysis, that's my guess too. You need only traces of sulfuric acid to make the pH low enough for the litmus to become red, and if it is diluted low density is quite normal.