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  2. 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.

  3. Silicon tetrachloride (data page) - Wikipedia

    en.wikipedia.org/wiki/Silicon_tetrachloride...

    Heat capacity, c p? J/(mol K) Liquid properties Std enthalpy change of formation, Δ f H o liquid: −687.0 kJ/mol Std Gibbs free energy of formation, Δ f G o liquid: −619.8 kJ/mol Standard molar entropy, S o liquid: 239.7 J/(mol K) Heat capacity, c p: 145. J/(mol K) Gas properties Std enthalpy change of formation, Δ f H o gas: −657. kJ ...

  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. 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 ...

  7. Chlorine - Wikipedia

    en.wikipedia.org/wiki/Chlorine

    Dichlorine heptoxide (Cl 2 O 7) is the anhydride of perchloric acid (HClO 4) and can readily be obtained from it by dehydrating it with phosphoric acid at −10 °C and then distilling the product at −35 °C and 1 mmHg. It is a shock-sensitive, colourless oily liquid.

  8. Gas chromatography–mass spectrometry - Wikipedia

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

    It is not possible to make an accurate identification of a particular molecule by gas chromatography or mass spectrometry alone. The mass spectrometry process normally requires a very pure sample while gas chromatography using a traditional detector (e.g. Flame ionization detector) cannot differentiate between multiple molecules that happen to ...

  9. Selected-ion flow-tube mass spectrometry - Wikipedia

    en.wikipedia.org/wiki/Selected-ion_flow-tube...

    In the selected ion flow tube mass spectrometer, SIFT-MS, ions are generated in a microwave plasma ion source, usually from a mixture of laboratory air and water vapor. . From the formed plasma, a single ionic species is selected using a quadrupole mass filter to act as "precursor ions" (also frequently referred to as primary or reagent ions in SIFT-MS and other processes involving chemical ...