What contains Hydrochloric acid?
If you have a cleaner that removes lime and rust, that cleaner will have strong acids in there. I can’t guarantee that it’s hydrochloric acid, but hydrochloric acid is one of the most common acids that there is. If all else fails, then you can make yourself puke because your stomach has quite a bit of hydrochloric acid in it, as well as organic (carbon-based) acids and digestive enzymes (proteins that make certain reactions go faster). (j/k don’t use puke for hydrochloric acid).
You can buy hydrochloric acid (20%) at most hardware stores, home centers, etc. They might be wary of selling it to minors. If you need a “story” say your dad sent you to pick up some to etch concrete. I suggest you also get a pair of safety glasses while you’re there so, when when something goes wrong and the acid goes splattering every where, you don’t trash your eyes.
