Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

10. (4 pts.) In this reaction you used observation of a precipitate as evidence

ID: 561168 • Letter: 1

Question

10. (4 pts.) In this reaction you used observation of a precipitate as evidence that reaction occurred. If there were no precipitate you would have had to isolate, purify and characterize the products of the reactions. This would have been a LOT OF WORK! But let's imagine that you did all of that for the reaction shown below, i.e. you isolated the iodide product of reaction of the bromide. Which analytical technique, mass spectrometry, infrared spectroscopy or proton NMR spectroscopy would you use to show that the iodide product is different from the bromide starting material, and that reaction occurred? Assume further that you don't have an authentic sample of the iodide product on hand to compare your spectra to. You need to show that the product is actually the iodide and not just that it is different form the starting bromide. Argue why the method you choose is best and why the other two methods are not as good. r: acetone

Explanation / Answer

Massspectroscopy technique is the best one to identify the iodide product formation in the given example.

Since, the molecular ion peaks are different for reactant ( bromide compound ) and for product ( iodide compound )

Molecular ion peak of the reactant i.e. bromide compound is appeared at m/z = 137

and, Molecular ion peak of the product i.e. iodide compound is appeared at m/z = 184