Question

How to differentiate bromine and chlorine on mass spectrometry?

A) By their unique fragmentation patterns
B) By their distinct ionization energies
C) By their characteristic isotope distributions
D) By their individual mass-to-charge ratios

Answer 1

To distinguish bromine and chlorine on mass spectrometry, the characteristic isotope distributions of each element are observed, revealing distinct patterns in the mass spectrum.

Step-by-step explanation:

To differentiate bromine (Br) and chlorine (Cl) on a mass spectrometer, the best approach would be to look at their characteristic isotope distributions. This choice is based on the distinct natural isotope patterns that each element exhibits. Chlorine has two major isotopes, 35Cl and 37Cl, with a natural abundance ratio of approximately 3:1, leading to a very characteristic pattern on a mass spectrum with two peaks separated by two mass units. Bromine also has two major isotopes, 79Br and 81Br, in an almost 1:1 ratio, which will show up as two peaks of roughly equal height separated by two mass units. Therefore, by examining the isotope distribution in the mass spectrum, chemists can readily distinguish between bromine and chlorine.