Qualitative analysis lab, zinc problem

AI Thread Summary
The discussion centers on a qualitative analysis lab where the unknown solution may contain various ions, including zinc. The participant has successfully identified all ions except zinc, which poses a challenge due to potential masking by other cations. They suggest using a flame test for zinc, though they express concerns about its practicality in a bright lab environment. The conversation invites suggestions on methods to isolate zinc from other cations to facilitate accurate testing. Effective strategies for distinguishing zinc without interference from other ions are sought.
will1530
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Homework Statement



This is for a qualitative analysis lab. The unknown solution can contain any combination of the following ions: Na, Mg, Ni, Cr, Zn, Ag, Pb, NO3, Cl, I, SO4

Tools available: Bunsen burner for flame test, centrifuge, hot plate, and all the test tubes and DI water you could possibly want.

Chemicals available to add: The Na+ or NO3- solutions for all the above ions, HNO3, HCl, NH3, NaOH, saturated AgSO4 solution, and 18M H2SO4.


The Attempt at a Solution



I have been able to figure out any combination of the above except for zinc. In every other cation qual lab we've had a known number of cations and the strategy was to simply figure out all the cations you can and if you have an extra slot throw zinc into it and you'll be correct if you did everything else right. Now we have to figure out a way to test for zinc that won't be masked by any other cations. The only thing I can think of is to try to flame test for it, but that doesn't seem very practical in a bright lab with other ions potentially in solution.
 
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will1530 said:

Homework Statement



This is for a qualitative analysis lab. The unknown solution can contain any combination of the following ions: Na, Mg, Ni, Cr, Zn, Ag, Pb, NO3, Cl, I, SO4

Tools available: Bunsen burner for flame test, centrifuge, hot plate, and all the test tubes and DI water you could possibly want.

Chemicals available to add: The Na+ or NO3- solutions for all the above ions, HNO3, HCl, NH3, NaOH, saturated AgSO4 solution, and 18M H2SO4.


The Attempt at a Solution



I have been able to figure out any combination of the above except for zinc. In every other cation qual lab we've had a known number of cations and the strategy was to simply figure out all the cations you can and if you have an extra slot throw zinc into it and you'll be correct if you did everything else right. Now we have to figure out a way to test for zinc that won't be masked by any other cations. The only thing I can think of is to try to flame test for it, but that doesn't seem very practical in a bright lab with other ions potentially in solution.

What have you done to remove the other cations?
 
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