Qualitative analysis lab, zinc problem

Click For Summary
SUMMARY

The discussion centers on a qualitative analysis lab focused on identifying zinc ions in a solution containing various cations such as Na, Mg, Ni, Cr, Ag, and Pb. The participant has successfully identified all other cations but struggles with zinc due to potential masking by other ions. They propose using a flame test, although they acknowledge its impracticality in a bright lab setting. The conversation emphasizes the need for a reliable method to isolate zinc without interference from other cations.

PREREQUISITES
  • Understanding of qualitative analysis techniques
  • Familiarity with flame tests and their limitations
  • Knowledge of common cation reactions with HNO3, HCl, and NH3
  • Experience with laboratory equipment such as centrifuges and hot plates
NEXT STEPS
  • Research methods for selectively precipitating zinc ions
  • Learn about complexation reactions involving zinc and other cations
  • Investigate the use of specific reagents to differentiate zinc from other cations
  • Explore advanced techniques such as ion chromatography for cation analysis
USEFUL FOR

Chemistry students, laboratory technicians, and educators involved in qualitative analysis and ion identification techniques.

will1530
Messages
1
Reaction score
0

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.
 
Physics news on Phys.org
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?
 

Similar threads

I with general unknown (qualitative analysis)
  • · Replies 5 ·
Replies
5
Views
7K
How Can I Identify Ions in a Mixture During a Practical Experiment?
  • · Replies 3 ·
Replies
3
Views
4K
How Can I Verify Results for My Grade 9 Science Experiment?
  • · Replies 4 ·
Replies
4
Views
8K
Pre-Lab Question: Identifying Acid with No Reaction to 8 Reactants
  • · Replies 1 ·
Replies
1
Views
2K
Separating Cations: AgNO3 + NH3?
  • · Replies 5 ·
Replies
5
Views
35K
Solve Net Ionic Equations: Chromium, Aluminium, Zinc
  • · Replies 15 ·
Replies
15
Views
8K