10 minutes is nowhere near enough time. Soak overnight or longer. You shouldn't need a grinder or a chisel. Dilute the acid with water, and don't forget to add the acid to the water and not the water to the acid.

Ok I'll give it a shot today to soak it longer. I was just following what the internet says literally everywhere...soak it for 5-10 minutes lol.

I also got a more powerful chuck drill from my buddy yesterday which will hopefully help

Remove it mechanically with a cup wheel on the grinder please. Build a wood jig to hold the tile.

I removed the old mastic etc of my 50 year old bathroom tiles by soaking overnight in an old crock pot (dont reuse the crock pot for food).

@Joseph Corlett, LLC

I have a cup wheel and I mounted a 3/4" drive to a beam to act that way, but i'll be damned if it isn't taking just as many dunks in the acid....at least its taking less grinding time i suppose