Why does hydrochloric acid not dissolve marble chips?

1 Answer
May 6, 2017

Is there a question here?


Anyway, this is a kinetic phenomenon. We can write the stoichiometric equation:

#CaCO_3(s) + 2HCl rarr CaCl_2(s) + H_2O(l) + CO_2(g)uarr#

Note that marble is a composite mixture of carbonate minerals, and here the composition #CaCO_3# is a reasonable approximation. #CaCO_3# is fairly insoluble in aqueous solution (most carbonates are!). And hence, if we grind up the marble finely, more surface area is exposed, and thus its reaction with added #HCl# should be more facile.