Two separate samples of bromine were analyzed by mass spectrometry
CHEMISTRY · Single correct · AP · Chemistry · Atomic Structure and Properties · Atomic Structure and Properties
Problem
Two separate samples of bromine were analyzed by mass spectrometry.
• Sample 1 shows two peaks at m/z=79 and m/z=81 with a relative intensity ratio of about 1:1.
• Sample 2 shows the same two peaks, but the peak at 81 is roughly four times taller than the peak at 79.
Which conclusion about Sample 2 is most strongly supported by these data?
(a) Sample 2 is enriched in the isotope 79Br.
(b) The unusually tall peak at m/z=81 arises from a significant impurity in the sample that also produces ions at that m/z value.
(c) Sample 2 has been enriched in the isotope 81Br relative to natural bromine.
(d) Many of the bromine ions in Sample 2 are doubly charged, causing the 81Br peak to appear four times more intense.