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Mass spectrum of pentan-2-one template
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Pentan-2-one EI mass spectrum sketch: M⁺• m/z 86, M − CH₃ m/z 71, McLafferty rearrangement m/z 58, CH₃CO⁺ base peak m/z 43, with the cleavage sites on the structure.
What the template shows
- EI (70 eV): molecular ion at m/z 86, α-cleavage to acylium ions (43, 71) and the McLafferty ion (58)
- EI mass spectrum (sketch) and fragmentation
- pentan-2-one, C₅H₁₀O, M = 86
- rel. abundance / %
- M⁺• (m/z 86) gives the molar mass: C₅H₁₀O = 86. The small M + 1 peak (m/z 87) comes from ¹³C (about 1.1 % per carbon, ~5.5 % of M here).
- α-Cleavage next to C=O gives resonance-stabilised acylium ions: loss of C₃H₇• → CH₃CO⁺ (m/z 43, base peak); loss of CH₃• → C₃H₇CO⁺ (m/z 71).
- McLafferty rearrangement: a γ-H moves to O through a six-membered ring and ethene (28) is lost → m/z 58 (the enol radical cation).
- Only ions are detected; the lost radicals and neutral molecules are worked out from the mass differences.
- Peak heights are illustrative; compare the measured spectrum (NIST WebBook) in the free MolDraw mass-spec viewer (moldraw.com/tools/mass-spec-viewer).
- Typical literature values; compare real spectra in SDBS · every part of this figure is editable
Drawn with 6 atoms, 44 shapes – every one editable in MolDraw.
Sources
How to use this template
- Press Edit in MolDraw. The template opens on the canvas of the free MolDraw editor.
- Change anything: move structures, edit atoms and labels, recolour highlights or delete what you do not need.
- Add your own structures, arrows and text next to it, or combine several templates on one page.
- Export the drawing as PNG, SVG or PDF for slides, worksheets, theses and papers.
Frequently asked questions
Is the Mass spectrum of pentan-2-one template free?
You can preview the Mass spectrum of pentan-2-one template here and open and edit it in MolDraw for free. Downloading or exporting it is part of MolDraw Pro, together with the other premium templates.
Can I edit the Mass spectrum of pentan-2-one template?
Yes. It opens as an ordinary MolDraw drawing, so every structure, arrow, label and colour can be changed, and you can add your own content around it.
Is the chemistry checked?
Every structure is checked with RDKit and every curly arrow passes MolDraw’s electron-flow audit. The sources used are listed on this page.
Are the spectra real data?
The spectra are schematic, drawn to the standard chemical shifts, splitting patterns and absorptions given in textbooks, so they are clear for teaching and exam practice.