Answer :
Final answer:
A white precipitate forms in the beaker containing silver nitrate (AgNO₃) when hydrochloric acid is added due to the formation of silver chloride (AgCl), which is sparingly soluble. Hence the correct option would be option 2.
Explanation:
The beaker which causes a white precipitate to form upon the addition of hydrochloric acid contains silver nitrate (AgNO₃). This reaction is due to the formation of silver chloride (AgCl), which is sparingly soluble in water and precipitates out of the solution as a white solid. The balanced chemical equation for this reaction is AgNO₃(aq) + HCl(aq) → AgCl(s)↓ + HNO₃(aq). Therefore, the correct answer is: 2) Beaker containing silver nitrate (KNO₃).