Question

Question 2
A solution reacts with crushed egg-shells to give a gas that turns lime-water milky. The solution contains:
1. NaCl
2. HCl
3. LiCl
4. KCl

Answer 1

The eggshells contain ${\text{CaCO}}_3$ which on reacting with $\text{HCl}$ solution gives out a gas that turns lime-water milky.
The reaction can be represented as: ${\text{CaCO}}_3+\text{HCl}\to {\text{CaCl}}_2+{\text{H}}_2\text{O}+{\text{CO}}_2\uparrow$