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Mass-to-Charge Ratio

  • Page ID
    40653
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    In mass spectroscopy, the mass-to-charge ratio (symbols: m/z, m/e) of a cation is equal to the mass of the cation divided by its charge.

    masstochargeratio1.png

    Since the charge of cation formed in the mass spectrometer is almost always +1, the mass-to-charge ratio of a cation is usually equal to the mass of the cation.

    masstochargeratio2.png

    The mass of the molecular ion is equal to the molecular weight of the compound. Thus, the mass-to-charge ratio of the molecular ion is equal to the molecular weight of the compound.


    This page titled Mass-to-Charge Ratio is shared under a All Rights Reserved (used with permission) license and was authored, remixed, and/or curated by Gamini Gunawardena via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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