Art chalk: how is it different [than normal chalk]?

what makes art chalk different?





i know it's softer and spreads better, probably breaks easy and is like more clay-e, but are there other things?





do you possibly know what makes it that way? like chemicals or ingredients?





but here's the one i need the answer to: IS ART CHALK MORE ACIDIC OR BASIC THAN NORMAL CHALK?

Art chalk: how is it different [than normal chalk]?
probably basic, so it doesnt yellow the paper or pics.