CHEM-252- ANALYTICAL CHEMISTRY LABORATORY
Analysis of Group I Cations
LAB REPORT
Instructors:
NAME & SURNAME:
ID:
Assistant:
DATE:
Section ( )
THE PURPOSE OF THE EXPERIMENT:
PROCEDURE(write down the experiment steps in order or draw a flowchart):
DATA AND CALCULATIONS( If any):
RESULTS AND DISCUSSION (experiment results, what reactions and separation technique you have
learned, write the reactions and the reagents and their properties etc. visuals about the experiment, if any)
CONCLUSION (your comments about the experiment, what you learned and the conclusion, etc.)
ANSWER TO THE QUESTIONS
1. Give the chemical formula and names of the first group cations?
2. Why are these classified as group 1 cations?
3. Why are group 1 cations precipitated in a little excess of HCl? Do group 1 cations also
precipitate with NaCl? Why HCl is prefereed but not NaCl?
4. Why too much HCl to be avoided during the precipitation of group 1 cations?
5. The Ksp values for Group I. chlorides are given at 25 ° C:
Kçç (Hg2Cl2) : 1.1 x 10
Kçç (AgCl)
: 1.8 x 10
Kçç (PbCl2)
: 1.7 x 10
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Use these values to answer the following questions.
a) What are the solubility’s of all three compounds at 25 ° C in mg / L ?
b) What is the most and least soluble compound?
c) Which one will first precipitate during the Group I analysis?
d) Which one will last precipitate?
6. The Ksp value for AgCl is given at 25 ° C. How many grams of AgNO3 is needed to start
precipitation of 100 mL of 0.01 M NaCl solution? Kçç (AgCl) : 1.8 x 10
REFERENCES
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