Had a bottle of that acid in my garage last fall Spence. I some how knocked it over and did not know I had done so till this past Spring. Of course the acid slowly leaked out of the bottle all winter. It ate one hell of a hole out of my concrete garage floor, the concrete was like mush where the acid layed all that time, made me sick. Pay attention to how you store it. Make sure you store it safely.[/align]
Rick that carbortor spray evaporates very rapidly and will cause the bottle to super cool you should be very careful touching the bottle until its warmed up to room temperature again or simply the temperature change from your skin could crack the bottle. If i was you go to home depot and get a gallon of muriatic acid and dilute it in about 3 gallons of water and let the flask soak for a couple hours in the acid bath. This should dissolve the black gunk.