The lead contained in a 0.2000 g sample is precipitated as PbCrO4. The precipitate is filtrated,...
The lead contained in a 0.2000 g sample is precipitated as PbCrO4. The precipitate is filtrated, washed and re-dissolved in acid to give lead ions and dichromate. 15.00 mL of 0.100 M FeSO4 is required to titrate the dichromate to the end point. Calculate the percentage of lead in the original sample.
Pb2+ + 2 CrO42- ===> PbCrO4(s)
2 PbCrO4 + 2 H+ ===> 2 Pb2+ + Cr2O72- + H2O
Cr2O72- + 6 Fe2+ + 14 H+ ===> 2 Cr3+ + 6 Fe3+ + 7 H2O
asnwer should be around 50%
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The lead contained in a 0.2000 g sample is precipitated as
PbCrO4. The precipitate is filtrated,...
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Please help. I will rate!
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I concluded that my unknown was Pb2+. since yellow precipitate formed. can you help me answer...
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Known and unknown report
Qualitative Analysis: Group I Cations 10 ORECTIVES A Leam some chemistry of Group I cations, R Analyze an unknown for Group I cations. THEORY AND DISCUSSION Group I cations are precipitated as insoluble chlorides: Ag, Pb, Hg2 +Cr-AgCl, PbCh, HgCla The colors of the following species will be helpful in the analysis for Group I cations....
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1. If your original unknown is colorless, what ions are absent
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pls help are my answers correct ty
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Please help. I will rate!
A 0.4721 g sample of pewter, containing tin, lead, copper, and zinc, was dissolved in acid. Tin was precipitated as SnO 4 H,O and removed by filtration. The resulting filtrate and washings were diluted to a total volume of 250.0 mL. A 15.00 mL aliquot of this solution was buffered, and titration of the lead, copper, and zinc in solution required 34.45 mL of 0.001518 M EDTA. Thiosulfate was used to mask the copper in...
I concluded that my unknown was Pb2+. since yellow
precipitate formed. can you help me answer the questions for the
Known and unknown report
Qualitative Analysis: Group I Cations 10 ORECTIVES A Leam some chemistry of Group I cations, R Analyze an unknown for Group I cations. THEORY AND DISCUSSION Group I cations are precipitated as insoluble chlorides: Ag, Pb, Hg2 +Cr-AgCl, PbCh, HgCla The colors of the following species will be helpful in the analysis for Group I cations....
1. If your original unknown is colorless, what ions are absent
from your unknown?
2. If you get no precipitate with just the 6 M NH3 in step B,
what ions are absent from your unknown?
pls help are my answers correct ty
17 Page 4 Aperiment 24. Qualitative Analysis Group III-NI, Mn, Fe, Al, Cr, Zn 1. PROCEDURES A. Observations of Samples. Obtain an unknown and record code. Observe color of unknown solution Common color correlations are: dark blue...
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