Fifty food supplement tablets with a total mass of 66.393 g were crushed into powder to analyse the content of FeSO4·7H2O. 2.988 g of the powder were dissolved in HNO3 and heated to convert all the iron to Fe3+. Addition of aqueous NH3 caused quantitative .precipitation of Fe2O3· X H2O, which was ignited to give 0.0640 g of Fe2O3. Determine the average weight of FeSO4·7H2O in each tablet.

Fifty food supplement tablets with a total mass of 66.393 g were crushed into powder to analyse the content of FeSO4·7H2O. 2.988 g of the powder were dissolved in HNO3 and heated to convert all the iron to Fe3+. Addition of aqueous NH3 caused quantitative .precipitation of Fe2O3· X H2O, which was ignited to give 0.0640 g of Fe2O3. Determine the average weight of FeSO4·7H2O in each tablet.

Chemistry by OpenStax (2015-05-04)

1st Edition

ISBN:9781938168390

Author:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark Blaser

Publisher:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark Blaser

Chapter18: Representative Metals, Metalloids, And Nonmetals

Section: Chapter Questions

Problem 115E: A mixture of xenon and ?uorine was heated. A sample of the white solid that formed reacted with...

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