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  2. Chemical impurity - Wikipedia

    en.wikipedia.org/wiki/Chemical_impurity

    In chemistry and materials science, impurities are chemical substances inside a confined amount of liquid, gas, or solid. They differ from the chemical composition of the material or compound. [ 1 ] Firstly, a pure chemical should appear in at least one chemical phase and can also be characterized by its phase diagram .

  3. 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 ...

  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. Liquid chromatography–mass spectrometry - Wikipedia

    en.wikipedia.org/wiki/Liquid_chromatography...

    Mass spectrometry (MS) is an analytical technique that measures the mass-to-charge ratio (m/z) of charged particles (ions). Although there are many different kinds of mass spectrometers, all of them make use of electric or magnetic fields to manipulate the motion of ions produced from an analyte of interest and determine their m/z. [18]

  6. Chemical purity - Wikipedia

    en.wikipedia.org/wiki/Chemical_purity

    In chemistry, chemical purity is the measurement of the amount of impurities found in a sample. Several grades of purity are used by the scientific, pharmaceutical, and industrial communities. [1] [2] Some of the commonly used grades of purity include:

  7. Mass spectrum - Wikipedia

    en.wikipedia.org/wiki/Mass_spectrum

    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 spectrometer. Not all mass spectra of a given substance are the same; for example, some mass spectrometers break the analyte molecules into fragments ; others observe the intact molecular ...

  8. Mass (mass spectrometry) - Wikipedia

    en.wikipedia.org/wiki/Mass_(mass_spectrometry)

    The mass defect used in nuclear physics is different from its use in mass spectrometry. In nuclear physics, the mass defect is the difference in the mass of a composite particle and the sum of the masses of its component parts. In mass spectrometry the mass defect is defined as the difference between the exact mass and the nearest integer mass.

  9. Chemical ionization - Wikipedia

    en.wikipedia.org/wiki/Chemical_ionization

    Peroxynitrate chemical ionization mass spectrometer at the US National Oceanic and Atmospheric Administration. CI mass spectrometry is a useful tool in structure elucidation of organic compounds. [3] This is possible with CI, because formation of [M+1] + eliminates a stable molecule, which can be used to guess the functional groups present. [3]