Question

Answer the question by selecting the appropriate option given below:

Assertion (A): The gas produced during the reaction of sodium carbonate with hydrochloric acid when passed through limewater, turns limewater milky.

Reason (R): Carbon dioxide reacts with limewater to form calcium hydrogen carbonate which forms a white precipitate.

[0.8 marks]

• A. Both A and R are true, and R is the correct explanation of A.
• B. Both A and R are true, and R is the correct explanation of A.
• C. A is true, but R is false.
• D. A is false, but R is true.

Answer 1

The correct option is C A is true, but R is false.

Sodium carbonate reacts with hydrochloric acid to produce sodium chloride, water, and carbon dioxide gas.

${\mathrm{Na}}_2{\mathrm{CO}}_3\left(\mathrm{aq}\right)+2\mathrm{HCl}\left(\mathrm{aq}\right)\to 2\mathrm{NaCl}\left(\mathrm{aq}\right)+H_{2}O\left(l\right)+{\mathrm{CO}}_2\left(g\right)$

This carbon dioxide gas when passed through limewater turns limewater milky.

Carbon dioxide reacts with limewater, i.e., calcium hydroxide to form calcium carbonate and not calcium hydrogen carbonate which forms a white precipitate.