A solution that may contain Cu2+ , Bi2+ , Sn4+ , or Sb2+ is treated with thioacetamide in an acidic medium. The black precipitate which forms is partly soluble in strongly basic solution. The precipitate which remains is soluble in 6 M HNO3 and gives only a white precipitate upon the addition of NH4OH. The basic solution, when acidified, produces an orange precipitate. Which group II ions are present? Which are absent? Which are in doubt? How would you remove all doubt?

A solution that may contain Cu2+ , Bi2+ , Sn4+ , or Sb2+ is treated with thioacetamide in an acidic medium. The black precipitate which forms is partly soluble in strongly basic solution. The precipitate which remains is soluble in 6 M HNO3 and gives only a white precipitate upon the addition of NH4OH. The basic solution, when acidified, produces an orange precipitate. Which group II ions are present? Which are absent? Which are in doubt? How would you remove all doubt?

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

Chapter37: Qualitative Analysis Of Group Ii Cations

Section: Chapter Questions

Problem 3ASA

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