Question 7 – Reactions of ions in aqueous solution (A-level only) - Questions

An aqueous solution of an unknown salt $X\,$ is analyzed using a series of qualitative tests:

Addition of dropwise aqueous sodium carbonate, $Na2CO3\text{Na}_2\text{CO}_3$ , to the solution produces a white precipitate and bubbles of a gas that turn limewater cloudy.
Addition of dropwise aqueous sodium hydroxide, $NaOH\text{NaOH}$ , to a separate portion of the solution produces a white precipitate which dissolves upon addition of excess sodium hydroxide to form a colorless solution.
Addition of dilute nitric acid followed by aqueous silver nitrate to a third portion of the solution produces a cream precipitate that is insoluble in dilute aqueous ammonia but dissolves when concentrated aqueous ammonia is added.

Which of the following is the correct formula of salt $X$ ?

An aqueous solution of an unknown salt $X\,$ is analyzed using a series of qualitative tests:

Addition of dropwise aqueous sodium carbonate, $Na2CO3\text{Na}_2\text{CO}_3$ , to the solution produces a white precipitate and bubbles of a gas that turn limewater cloudy.
Addition of dropwise aqueous sodium hydroxide, $NaOH\text{NaOH}$ , to a separate portion of the solution produces a white precipitate which dissolves upon addition of excess sodium hydroxide to form a colorless solution.
Addition of dilute nitric acid followed by aqueous silver nitrate to a third portion of the solution produces a cream precipitate that is insoluble in dilute aqueous ammonia but dissolves when concentrated aqueous ammonia is added.

Which of the following is the correct formula of salt $X$ ?

Reactions of ions in aqueous solution (A-level only)