Write an activity to show the reaction of acids with metal carbonates and metal hydrogen carbonate salts.

Explanation

Take two test tubes. Mark them as 'A' and 'B'. Take about 0.5 gm of sodium carbonate in the test tube 'A' and 0.5 gm of sodium hydrogen carbonate in test tube 'B'. Add about 2 ml of dilute HCl acid to both of these test tubes. Pass the gas produced in each case through lime water as shown in the figure. Lime water in each case will turn milky due to the production of `CO_(2)` gas in each of the test tubes.

Reaction occurring in the above activity :
Test tube 'A' `Na_(2)CO_(3)(s)+2HCl (aq) rarr 2NACl (aq)+CO_(2) (g)+H_(2)O(l)`
Test tube 'B' `NaHCO_(3) (s)+HCl (aq) rarr NaCl (aq)+CO_(2) (g) +H_(2)O (l)`
On passing the gas evolved through the lime water :
`underset("lime water")(Ca(OH)_(2)(aq))+CO_(2) (g) rarr underset(("white ppt."),("(milkiness)"))(CaCO_(3) (s))+H_(2)O`
But on passing excess `CO_(2)` gas through the lime water, milkiness disappears due to the formation of soluble `CaHCO_(3)`
`CaCO_(3)+CO_(2)+H_(2)O rarr underset("Calcium hydrogen-carbonate")(Ca(HCO_(3))_(2) (aq))`
this activity shows that metal carbonates and metal hydrogen carbonate react with acids to form salt, `CO_(2)` and water.