Effect of Isotopes Can distinguish atoms by the ratio of peaks above the molecular ion Especially useful to distinguish which halogen is present Br 人 m/z78 m/z122 m/z170 M/M+2=3 M/M+2=1 100 h3--4951 80 60 40 M/M+2卡1 20 0-tmmpmttrprtimm mmmmjmmphmttimmmmmmmpmmirtpmmmmr 10 20 30 40 50 60708090100110120 m/z Can distinguish atoms by the ratio of peaks above the molecular ion Especially useful to distinguish which halogen is present Cl Br I m/z 78 M/M+2 = 3 ~ 3/1 m/z 122 M/M+2 = 1 M/M+2 = 1 m/z 170 Effect of Isotopes