Question

a solution reacts with crushed egg shells to give a gas that turns lime water milky . the solution contains__________

Answer 1

The solution is HCl.

Egg shells contains calcium carbonate, which on reaction with HCl liberates CO2 gas which turn lime water to milky.

CaCO3 + 2HCl → CaCl2 + H2O + CO2

Answer 2

Question :

A solution produces a gas by reacting with egg shells, which turns lime water to milky. What will happen in this solution?  

ANSWER :

Hydrogen chloride

Lime water turns milky and hence the gas is carbon-dioxide.

We already know that egg shells contain calcium carbonate .

Hence the only thing that can displace is HCl .

Thus the answer is HCl as only an acid can perform the above reaction and displace the calcium carbonate to liberate an acidic gas.

Reaction :

CaCO₃ + 2HCl → CaCl₂ + H₂O + CO₂