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  2. Mass spectrum - Wikipedia

    en.wikipedia.org/wiki/Mass_spectrum

    Electron ionization mass spectrum of toluene. Note parent peak corresponding to molecular mass M = 92 (C 7 H 8 +) and highest peak at M-1 = 91 (C 7 H 7 +, quasi-stable tropylium cation). A mass spectrum is a histogram plot of intensity vs. mass-to-charge ratio (m/z) in a chemical sample, [1] usually acquired using an instrument called a mass ...

  3. Chloroacetonitrile - Wikipedia

    en.wikipedia.org/wiki/Chloroacetonitrile

    The compound is an alkylating agent, [2] and as such is handled cautiously. Chloroacetonitrile is also generated in situ by the reaction of acetonitrile with sulfur monochloride . A second chlorination gives dichloro acetonitrile , which undergoes cycloaddition with sulfur monochloride to give 4,5-dichloro-1,2,3-dithiazolium chloride : [ 3 ]

  4. Mass spectrometry - Wikipedia

    en.wikipedia.org/wiki/Mass_spectrometry

    Ion mobility spectrometry-mass spectrometry (IMS/MS or IMMS) is a technique where ions are first separated by drift time through some neutral gas under an applied electrical potential gradient before being introduced into a mass spectrometer. [43] Drift time is a measure of the collisional cross section relative to the charge of the ion.

  5. Mass spectral interpretation - Wikipedia

    en.wikipedia.org/wiki/Mass_spectral_interpretation

    The mass spectrum of methylbromide has two prominent peaks of equal intensity at m/z 94 (M) and 96 (M+2) and then two more at 79 and 81 belonging to the bromine fragment. Even when compounds only contain elements with less intense isotope peaks ( carbon or oxygen ), the distribution of these peaks can be used to assign the spectrum to the ...

  6. Mass chromatogram - Wikipedia

    en.wikipedia.org/wiki/Mass_chromatogram

    A mass chromatogram is a representation of mass spectrometry data as a chromatogram, where the x-axis represents time and the y-axis represents signal intensity. [1] The source data contains mass information; however, it is not graphically represented in a mass chromatogram in favor of visualizing signal intensity versus time.

  7. Direct analysis in real time - Wikipedia

    en.wikipedia.org/wiki/Direct_analysis_in_real_time

    In mass spectrometry, direct analysis in real time (DART) is an ion source that produces electronically or vibronically excited-state species from gases such as helium, argon, or nitrogen that ionize atmospheric molecules or dopant molecules. The ions generated from atmospheric or dopant molecules undergo ion-molecule reactions with the sample ...

  8. Collision-induced dissociation - Wikipedia

    en.wikipedia.org/wiki/Collision-induced_dissociation

    Trapped fragment ions or their ion-molecule reaction products can be re-excited for multistage mass spectrometry (MS n). [5] If the excitation is not applied on the resonant frequency, but at a slightly off-resonant frequency, the ions will alternately be excited and de-excited, permitting multiple collisions at low collision energy.

  9. Isotopes of chlorine - Wikipedia

    en.wikipedia.org/wiki/Isotopes_of_chlorine

    Chlorine (17 Cl) has 25 isotopes, ranging from 28 Cl to 52 Cl, and two isomers, 34m Cl and 38m Cl. There are two stable isotopes, 35 Cl (75.8%) and 37 Cl (24.2%), giving chlorine a standard atomic weight of 35.45.