3. To study the reaction of metal carbonate/hydrogen carbonate with acid.

AIM:- To study the reaction of metal carbonate/hydrogen carbonate with acid.

APPARATUS REQUIRED:- Test tube stand, Two test tube, Delivery tube, Spatula, Dilute hydrochloric acid, Lime water, Sodium hydrogen carbonate.

PROCEDURE:-

1. Take a test tube and clamp it on the test tube stand . Put a small amount of sodium hydrogen carbonate in it.
2. In other test tube pour about 3-4 ml lime water
3. Add about 2 ml of dilute hydrochloric acid into the test tube contains sodium hydrogen carbonate and close the mouth of the test tube with a cork fitted with delivery tube .
4. Pass the gas evolved into the lime water and note your observation.

Passing carbon dioxide gas through calcium hydroxide solution

OBSERVATION:- When dilute hydrochloric acid is added to the sodium hydrogen carbonate, a brisk reaction takes place as a result salt water and carbon dioxide gas are formed. When we pass carbon dioxide gas through lime water it turns milky due to the formation of insoluble calcium carbonate. When the gas is continuously passed, the milkiness disappear due to formation of soluble calcium hydrogen carbonate.

CONCLUSION:- Hence from the above observations we can conclude that metal carbonate and hydrogen carbonate react with acid to give corresponding salt, water and carbon dioxide gas.

REACTION:- 

Ca(OH)₂^(ag) +  CO₂  à CaCO_{3 +}H₂O

(Lime water)

CaCO₃^(s) + H₂O^(l) + CO₂ ^(g) à Ca(HCO₃)₂

                                          (soluble in water)

NaHCO₃^(s)  + HCL ^(aq)  à NaCl^(aq) + H₂O^(l) + CO₂^(g)