Identify the element from its mass spectrum

An example figure from the Mass Spectrum generator.

An unnamed element’s mass spectrum with two nearly equal peaks at m/z 79 and 81, labeled 50.69% and 49.31% — The mass spectrum of an unnamed element, for students to identify: two nearly equal peaks at m/z 79 and 81, labeled with their percent abundances. The weighted average mass is about 79.9, which is bromine.

Edit this figure Download PNG

Editing opens it in Mass Spectrum with these settings, to change anything and copy or download your own.

Answer key

Bromine (Br): relative atomic mass 79.90
Relative atomic mass: (78.918 × 50.69 + 80.916 × 49.31) ÷ 100 = 79.90

Free to use in your tests, worksheets, slides or anything else. Open source under Apache 2.0. How to reuse our figures

More Mass Spectrum examples

Make your own in Mass Spectrum →