Question

What happens when nitric acid is added to the eggshell?

Answer 1

Eggshell: It is almost completely made up of calcium carbonate ${\mathrm{CaCO}}_3$ crystals. Air and moisture are able to pass through its pores since it is a semipermeable membrane.

• When nitric acid is added to eggshells $\left({\mathrm{CaCO}}_3\right)$, it produces calcium nitrate and carbon-di-oxide gas.

$\underset{\mathrm{Eggshell}}{{\mathrm{CaCO}}_3(\mathrm{s}})+\underset{\mathrm{Nitric}\mathrm{Acid}}{2{\mathrm{HNO}}_3\left(\mathrm{aq}\right)}\to \underset{\mathrm{Calcium}\mathrm{Nitrate}}{\mathrm{Ca}{\left({\mathrm{NO}}_3\right)}_2\left(\mathrm{aq}\right)}+\underset{\mathrm{Carbon}\mathrm{dioxide}}{{\mathrm{CO}}_2(\mathrm{g}})+\underset{\mathrm{Water}}{{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}$

Final answer: when Nitric acid is added to eggshells $\left({\mathrm{CaCO}}_3\right)$, it produces calcium nitrate and carbon-di-oxide gas.