What happens when nitric acid is added to egg shell?

Nitric acid dissolved the egg shell, which is made up of Calcium carbonate. Calcium carbonate, on reacting with nitric acid, yields calcium nitrate and carbon dioxide gas.

When nitric acid is added to an eggshell:

• The eggshell is mainly made of calcium carbonate (CaCO₃).
• Nitric acid reacts with calcium carbonate in a chemical reaction.

What happens:

• The eggshell starts fizzing (bubbling).
• Carbon dioxide gas (CO₂) is released.
• The shell gradually dissolves.

Chemical reaction:

CaCO3+2HNO3→Ca(NO3)2+CO2+H2O

Final result:

• The hard shell gets eaten away.
• A soft membrane underneath may remain. In short: Nitric acid reacts with the eggshell, producing bubbles and dissolving the shell.