Chemical Reactions:
Marble is calcium carbonate. It reacts with HCl to give CO2
CaCO3 + 2HCl CaCl2 + CO2 + H2O
Marble (A)
CO2 when passed through lime water [Ca(OH)2] gives a white precipitate of CaCO3.
Ca(OH)2 + CO2(g) CaCO3(s) + H2O
White ppt.
(B)
On passing excess CO2, CaCO3 dissolves forming soluble Ca(HCO3)2.
CaCO3 + CO2 Ca(HCO3)2 (aq)
Calcium
hydrogen
carbonate
(C)
A — Carbon dioxide
B — Calcium carbonate
C — Calcium hydrogen carbonate