Question

A solution contains 0.1 M Sr2+ ions and 0.1 M Ag+ ions. Addition of an equal volume of a 0.5 M solution of which reagent will cause precipitation of a strontium salt but not a silver salt? (A) NaNO3 (B) NaF (C) NaOH (D) NaCl.

Answer 1

The correct answer should be the option B - NaF.

When Sodium Fluoride (NaF) is added to the solution containing the Sr²⁺ ions and the Ag⁺ ions, the fluoride ions will react with the Sr²⁺ ions instead of the Ag⁺ ions and will form a precipitate of SrF₂ (Strontium fluoride).