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  2. Standard addition - Wikipedia

    en.wikipedia.org/wiki/Standard_addition

    To apply this method, analysts prepare multiple solutions containing equal amounts of unknown and spike them with varying concentrations of the analyte. The amount of unknown and the total volume are the same across the standards and the only difference between the standards is the amount of analyte spiked.

  3. Internal standard - Wikipedia

    en.wikipedia.org/wiki/Internal_standard

    Suppose there are known concentrations of nickel in a set of calibration solutions: 0 ppm, 1.6 ppm, 3.2 ppm, 4.8 ppm, 6.4 ppm, and 8 ppm. Each solution also has 5 ppm yttrium to act as an internal standard. If these solutions are measured using ICP-OES, the intensity of the yttrium signal should be consistent across all solutions.

  4. Mass spectrometry - Wikipedia

    en.wikipedia.org/wiki/Mass_spectrometry

    There are many mass/charge separation and isolation methods but the most commonly used is the mass instability mode in which the RF potential is ramped so that the orbit of ions with a mass a > b are stable while ions with mass b become unstable and are ejected on the z-axis onto a detector. There are also non-destructive analysis methods.

  5. Resolution (mass spectrometry) - Wikipedia

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

    Some mass spectrometrists use the definition that is similar to definitions used in some other fields of physics and chemistry. In this case, resolving power is defined as: R = M Δ M = r e s o l v i n g p o w e r {\displaystyle R={\cfrac {M}{\Delta M}}=\mathrm {resolving\ power} }

  6. Response factor - Wikipedia

    en.wikipedia.org/wiki/Response_factor

    The response factor can be expressed on a molar, volume or mass [1] basis. Where the true amount of sample and standard are equal: = where A is the signal (e.g. peak area) and the subscript i indicates the sample and the subscript st indicates the standard. [2]

  7. Parts-per notation - Wikipedia

    en.wikipedia.org/wiki/Parts-per_notation

    At 1 ppm the solution is a very pale yellow. As the concentration increases the colour becomes a more vibrant yellow, then orange, with the final 10,000 ppm a deep red colour. In science and engineering , the parts-per notation is a set of pseudo-units to describe small values of miscellaneous dimensionless quantities , e.g. mole fraction or ...

  8. Mass (mass spectrometry) - Wikipedia

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

    The Kendrick mass is a mass obtained by multiplying the measured mass by a numeric factor. The Kendrick mass is used to aid in the identification of molecules of similar chemical structure from peaks in mass spectra. [16] [17] The method of stating mass was suggested in 1963 by the chemist Edward Kendrick.

  9. Mass concentration (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Mass_concentration_(chemistry)

    In solutions, mass concentration is commonly encountered as the ratio of mass/[volume solution], or m/v. In water solutions containing relatively small quantities of dissolved solute (as in biology), such figures may be "percentivized" by multiplying by 100 a ratio of grams solute per mL solution. The result is given as "mass/volume percentage".