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0 of 4 missions completed. Current mission: Ion Source. Ionize a sample and observe mass separation.

Mass Spectrometry Lab

Mass Spectrometry Simulator – Free Online MS Lab

Mass spectrometry separates ionized molecules by mass-to-charge ratio (m/z), producing a spectrum of fragment ions that act as a molecular fingerprint. This simulation walks you through ionization, mass separation, and detection, letting you interpret spectra of organic molecules and practice recognizing base peaks, molecular ion peaks, and fragmentation patterns.

What you can do in this simulation

  • Select organic molecules and generate their simulated EI or ESI mass spectra
  • Identify the molecular ion peak (M⁺) and calculate the molecular formula from exact mass
  • Trace common fragmentation pathways including alpha-cleavage and McLafferty rearrangement
  • Interpret isotope patterns for molecules containing chlorine or bromine
  • Match an unknown spectrum against reference spectra for structure identification

Concepts covered

mass-to-charge ratio m/z · molecular ion peak · fragmentation pattern · electron ionization · isotope pattern · base peak

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