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 and no precipitate formed. 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*, Pb²+, Hgž+ form insoluble chlorides Bi3+, Cd²+, Cu²+, Hg²+, Pb2+, Sb³+, Sn²+, Snª+ form acid-insoluble sulfides Al3+, Co²+, Cr³+, Fe²+, form base-insoluble sulfides or hydroxides Fe3+, Ni?+, Mn²+, Zn²+ Ba?+, Ca2+, Mg²+, Sr²+ form insoluble carbonates Lit, Na*, K*, NH completely soluble Answer Bank None of these ions were present. unknown At least one of these ions was present. All 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 and no precipitate formed. 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, Pb²+, Hgž+ form insoluble chlorides Bi3+, Cd²+, Cu²+, Hg²+, Pb2+, Sb³+, Sn²+, Snª+ form acid-insoluble sulfides Al3+, Co²+, Cr³+, Fe²+, form base-insoluble sulfides or hydroxides Fe3+, Ni?+, Mn²+, Zn²+ Ba?+, Ca2+, Mg²+, Sr²+ form insoluble carbonates Lit, Na, K*, NH completely soluble Answer Bank None of these ions were present. unknown At least one of these ions was present. All of these ions were present.

Chemical Principles in the Laboratory

11th Edition

ISBN:9781305264434

Author:Emil Slowinski, Wayne C. Wolsey, Robert Rossi

Publisher:Emil Slowinski, Wayne C. Wolsey, Robert Rossi

Chapter27: Relative Stabilities Of Complex Ions And Precipitates Prepared From Solutions Of Copper(ii)

Section: Chapter Questions

Problem 1ASA

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