A solution may contain Ag + , Pb 2+ , Al 3+ , Fe 3+ , and Mn 2+ ions. Upon addit

Question

A solution may contain Ag+, Pb2+, Al3+, Fe3+, and Mn2+ ions. Upon addition of 6M HCL no precipitate formed. However, a precipitate (solid B) formed after the solution was made slightly basic. After decanting, 6M NaOH was added to the solution until strongly basic that resulted in a fraction of solid B dissolving. The resulting solution was then decanted from solid B. The solution was made slightly acidic that yileded a white precipitate. Solid B dissolved upon treatment with nitric acid to form solution C that was then divided between two test tubes. Solution C turned a dark red in the prescence of KSCN. Which ion(s) are present, which are absent, or which may remain undetermined? Indicate if any test(s) are needed to verify the prescence of the undetermined ion.

Explanation / Answer

Ag+, Pb2+, Al3+, Fe3+, and Mn2+----------6M HCl---------> AgCl (precipitate)

Pb2+, Al3+, Fe3+, and Mn2+ ---------H2S acidic solution------> Pb+2 (precipitate)

Al3+, Fe3+, and Mn2+ ---------H2S basic solution------> Mn+2 (precipitate)

Al3+, Fe3+ ---------6M NaOH/3% H2O2 -----> Fe(OH)3 (brown)

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.