A lab student analyzed his/her cool nickel-en complex for ethylenediamine, en, content. A 0.515 g sample of the synthesized Ni-en complex was dissolved in about 50 mL of water and titrated with 0.186 M HCI (ag). Endpoint required 20.16 mL of the HCl (ag). 0.113 grams en in the Ni-en complex analyzed. 40 mL of dimethylglyoxime, DMG, solution was added to the titrated nickel-en complex solution. The resulting beautiful red complex, Ni(DMG)2 was collected by filtration and found to weigh 0.419 g What is the mass (in grams) of Ni in the Ni-en complex analyzed? Determine the empirical formula of the complex synthesized in questions

A lab student analyzed his/her cool nickel-en complex for ethylenediamine, en, content. A 0.515 g sample of the synthesized Ni-en complex was dissolved in about 50 mL of water and titrated with 0.186 M HCI (ag). Endpoint required 20.16 mL of the HCl (ag). 0.113 grams en in the Ni-en complex analyzed. 40 mL of dimethylglyoxime, DMG, solution was added to the titrated nickel-en complex solution. The resulting beautiful red complex, Ni(DMG)2 was collected by filtration and found to weigh 0.419 g What is the mass (in grams) of Ni in the Ni-en complex analyzed? Determine the empirical formula of the complex synthesized in questions

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter17: Complexation And Precipitation Reactions And Titrations

Section: Chapter Questions

Problem 17.42QAP

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An alloy containing Ni, Fe and Cr was analyzed by a complexation titration using EDTA as titrant. A 0.7176 g sample of the alloy was dissolved in HNO3 and diluted to 250 mL in a flask. A 50.00 mL aliquot of the sample, treated with pyrophosphate to mask Fe and Cr, required 26.14 mL of 0.05831 M EDTA to reach the murexide endpoint. A second 50.00 mL aliquot was treated with hexamethylenetetramine to mask Cr and titration with 0.05831 M EDTA required 35.43 mL to reach the murexide endpoint. Finally, a third 50.00 mL aliquot was treated with 50.00 mL of 0.05831 M EDTA and titrated back to the murexide endpoint with 6.21 mL of 0.06316 M Cu(II). the weight percentages of Ni, Fe and Cr in the alloy.