When dilute hydrochloric acid is placed on fock limestone and the non-sedimentary rock marble, a bubbling reaction occurs with both. What would this indicate?

1 Answer
Dec 22, 2017

Both limestone and marble are forms of calcium carbonate.... And the bubbling indicates the evolution a gas, but which one?


And calcium carbonate, pretty insoluble stuff, undergoes a reaction with strong acids:

#CaCO_3(s) +2HCl(aq)rarrCaCl_2(aq) + H_2O(l) + CO_2(g)uarr#

And of course liberation of carbon dioxide would account for the bubbling observed in the reaction.

The gases that bubbled off the reaction could be bled into a solution of lime-water, i.e. #Ca(OH)_2(aq)#...and the carbonate would reprecipitate...

#CO_2(g) + Ca(OH)_2(aq) rarr CaCO_3(s)darr + H_2O(l)#

Surely you have done practicals to examine these reactions?