A student dropped a few pieces of marble in dilute hydrochloric acid, contained in a test tube, the evolved gas was then passed for a long time through lime water. What changes would be observed in lime water ? Write balanced equations for both the changes observed.

A student dropped a few pieces of marble in dilute hydrochloric acid,

1.	A student dropped a few pieces of marble in dilute hydrochloric acid, contained in a test tube, the evolved gas was then passed for a long time through lime water. What changes would be observed in lime water ? Write balanced equations for both the changes observed.
Answer» Solution :On adding pieces of MARBLE is the test tube containing dil. HCl a brisk evolution of `CO_(2)` takes palce. Carbon dioxide when passed through lime water turns it milky because of the FORMATION of insolube calcium carbonate. `CaCO_(3)(s) +2HCl (aq) rarr CaCl_(2)(aq) + CO_(2)(g) +H_(2)O(l)` `UNDERSET("Lime water")(Ca(OH)_2) + CO_2 rarr underset("(milky)")underset("carbonate")underset("Calcium")(CaCO_3 + H_(2)O` (II) If `CO_2` is continuosly passed for a long time , the milkiness disappears due to the formation of soluble sodium hydrogencarbonate. `CaCO_(3)+CO_(2)+H_(2)O rarr underset("saluble")(Ca(HCO_3))_2`