A solution containing a mixture of metal cations was treated as outlined. 1. Dilute HCl was added and a precipitate formed. The precipitate was filtered off. 2. H,S was bubbled through the acidic solution. No precipitate formed. 3. The pH was raised to about 9 and H,S was again bubbled through the solution. A precipitate formed and was filtered off. 4. Finally, sodium carbonate was added to the filtered solution. A precipitate formed and was filtered off. What can be said about the presence of each of these groups of cations in the original solution? Cation group Description Present in the original solution? Ag+, Pb?+, Hg3+ ,2+ form insoluble chlorides Bi3+, Cd²+, Cu²+, Hg²+, Pb2+, Sb3+, Sn²+, Sn++ Al3+, Co2+, Cr3+, Fe2+, Fe3+, Ni2+, Mn2+, Zn²+ form acid-insoluble sulfides form base-insoluble sulfides or hydroxides Ba2+, Ca2+, Mg²+, Sr²+ form insoluble carbonates Lit, Na*, K*, NH completely soluble Answer Bank unknown At least one of these ions was present. All of these ions were present. None of these ions were present.

A solution containing a mixture of metal cations was treated as outlined. 1. Dilute HCl was added and a precipitate formed. The precipitate was filtered off. 2. H,S was bubbled through the acidic solution. No precipitate formed. 3. The pH was raised to about 9 and H,S was again bubbled through the solution. A precipitate formed and was filtered off. 4. Finally, sodium carbonate was added to the filtered solution. A precipitate formed and was filtered off. What can be said about the presence of each of these groups of cations in the original solution? Cation group Description Present in the original solution? Ag+, Pb?+, Hg3+ ,2+ form insoluble chlorides Bi3+, Cd²+, Cu²+, Hg²+, Pb2+, Sb3+, Sn²+, Sn++ Al3+, Co2+, Cr3+, Fe2+, Fe3+, Ni2+, Mn2+, Zn²+ form acid-insoluble sulfides form base-insoluble sulfides or hydroxides Ba2+, Ca2+, Mg²+, Sr²+ form insoluble carbonates Lit, Na, K, NH completely soluble Answer Bank unknown At least one of these ions was present. All of these ions were present. None of these ions were present.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter17: Complexation And Precipitation Reactions And Titrations

Section: Chapter Questions

Problem 17.34QAP

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