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  2. 4-Chlorobenzaldehyde - Wikipedia

    en.wikipedia.org/wiki/4-Chlorobenzaldehyde

    clc 5 h 4 chcl 2 + h 2 o → clc 5 h 4 cho + 2 hcl It can also be produced by the oxidation of 4-chlorobenzyl alcohol . [ 3 ] [ 4 ] It can be further oxidized to 4-chlorobenzoic acid . [ 5 ]

  3. Sample preparation in mass spectrometry - Wikipedia

    en.wikipedia.org/wiki/Sample_preparation_in_mass...

    [4] [5] Mass spectrometry ionization techniques requiring the sample to be in the gas phase have similar concerns. Electron ionization (EI) in mass spectrometry requires samples that are small molecules, volatile, and thermally stable, similar to that of gas chromatography. This ensures that as long as GC is performed on the sample before ...

  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

    [1] [2] Mass spectra is a plot of relative abundance against mass-to-charge ratio. It is commonly used for the identification of organic compounds from electron ionization mass spectrometry. [3] [4] Organic chemists obtain mass spectra of chemical compounds as part of structure elucidation and the analysis is part of many organic chemistry ...

  6. Benzyl chloride - Wikipedia

    en.wikipedia.org/wiki/Benzyl_chloride

    Benzoic acid (C 6 H 5 COOH) can be prepared by oxidation of benzyl chloride in the presence of alkaline KMnO 4: C 6 H 5 CH 2 Cl + 2 KOH + 2 [O] → C 6 H 5 COOK + KCl + H 2 O Benzyl chloride may be used in the synthesis of amphetamine-class drugs, and for this reason, sales of benzyl chloride are monitored as a List II drug precursor chemical ...

  7. Gas chromatography–mass spectrometry - Wikipedia

    en.wikipedia.org/wiki/Gas_chromatography–mass...

    [4] [5] An interest in coupling the methods had been suggested as early as December 1954, [6] but conventional recording techniques had too poor temporal resolution. Fortunately, time-of-flight mass spectrometry developed around the same time allowed to measure spectra thousands times a second. [7]

  8. Selected reaction monitoring - Wikipedia

    en.wikipedia.org/wiki/Selected_reaction_monitoring

    The ion is selected in the second mass spectrometry stage MS2 then undergoes further fragmentation to form ion D + which is selected in the third mass spectrometry stage MS3 and detected. Multiple reaction monitoring ( MRM ) is the application of selected reaction monitoring to multiple product ions from one or more precursor ions, [ 3 ] [ 4 ...

  9. Isotope dilution - Wikipedia

    en.wikipedia.org/wiki/Isotope_dilution

    Calibration curves are obtained by plotting measured isotope ratios in the prepared blends against the known ratio of the sample mass to the mass of the spike solution in each blend. Isotope dilution calibration plots sometimes show nonlinear relationships and in practice polynomial fitting is often performed to empirically describe such curves ...