My house was decorated in the 1970's and had a plaster applied around a
stove to look like bricks. I removed the stove and needed to get rid of
the faux brick. The drywall was easy because I just replaced it. I tried
chiselling the plaster off the concrete floor. After several evenings of
strong arms I searched the Internet. Lots of people recommended muriatic
acid or vinegar. One chemist recommended baking soda (sodium bicarbonate)
in a water solution. I tried that because he explained the chemical
reaction with the sulfur and sodium. It worked. I let the baking soda
solution soak about a half hour and a putty knife took it off easily.
Thank you chemist.

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