Why does calcium carbonate undergo mass loss upon heating?

1 Answer
Dec 30, 2016

Because of gas evolution...


#CaCO_3(s) + Delta rarr CaO(s) + CO_2(g)uarr#

Clearly, the carbonate is decomposed, with concomitant loss of mass as carbon dioxide gas. Typically, the product gas will be shunted to a solution of lime water (#Ca(OH)_2#), where the carbonate will be reconstituted:

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

Are mass and charge conserved in both reactions? Should they be?