A solution reacts with crushed eggshells to give a gas that turns limewater milky. The solution contains

Correct option is B

The correct answer is HCl.

• Eggshells are made up of calcium carbonate.
• When Calcium carbonate reacts with Hydrochloric acid it liberates carbon dioxide gas.
• The carbon dioxide gas turns lime-water milky.
• The reaction can be represented as:
• CaCO₃+2HCl→CaCl₂+H₂O+CO₂
• Ca(OH)₂+CO₂→CaCO₃+H₂O
• When carbon dioxide gas reacts with calcium hydroxide (Ca(OH)₂) solution then it produces a white precipitate of calcium carbonate, hence the solution turns milky.