fossilesque@mander.xyzM to Science Memes@mander.xyzEnglish · edit-210 months ago[Partially incorrect, see comments.] Pens in Spacemander.xyzimagemessage-square148fedilinkarrow-up11.48K
arrow-up11.48Kimage[Partially incorrect, see comments.] Pens in Spacemander.xyzfossilesque@mander.xyzM to Science Memes@mander.xyzEnglish · edit-210 months agomessage-square148fedilink
minus-squareArcka@midwest.sociallinkfedilinkEnglisharrow-up5·10 months agoRegular chalk is calcium carbonate. Crayola’s website says their sidewalk chalk uses calcium sulfate (gypsum as an ingredient in plaster of paris). So they’re both calcium salts.
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Regular chalk is calcium carbonate. Crayola’s website says their sidewalk chalk uses calcium sulfate (gypsum as an ingredient in plaster of paris).
So they’re both calcium salts.