1.) A student was asked to identify an unknown hydrate by following the procedure described in this module. After heating and cooling, a 2.752 gram sample of this unknown weighed 1.941 grams. Students were given a list of possible compounds from which to identify their unknowns: LINO3 3H20, Ca(NO,)2•4H20, and Sr(NO3)2•4H20. a.) Calculate the percent water in the student's unknown. b.) Could the unknown possibly have been Sr(NO)2•4H,0? Briefly explain. Show work. c.) What is the probable identify of the student's unknown? d.) Based o the student's results and your answer to c., what is the most probable source of error in the experiment?

1.) A student was asked to identify an unknown hydrate by following the procedure described in this module. After heating and cooling, a 2.752 gram sample of this unknown weighed 1.941 grams. Students were given a list of possible compounds from which to identify their unknowns: LINO3 3H20, Ca(NO,)2•4H20, and Sr(NO3)2•4H20. a.) Calculate the percent water in the student's unknown. b.) Could the unknown possibly have been Sr(NO)2•4H,0? Briefly explain. Show work. c.) What is the probable identify of the student's unknown? d.) Based o the student's results and your answer to c., what is the most probable source of error in the experiment?

Chemistry for Engineering Students

4th Edition

ISBN:9781337398909

Author:Lawrence S. Brown, Tom Holme

Publisher:Lawrence S. Brown, Tom Holme

Chapter4: Stoichiometry

Section: Chapter Questions

Problem 4.58PAE

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