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  2. Paper chromatography - Wikipedia

    en.wikipedia.org/wiki/Paper_chromatography

    Paper chromatography is a useful technique because it is relatively quick and requires only small quantities of material. Separations in paper chromatography involve the principle of partition. In paper chromatography, substances are distributed between a stationary phase and a mobile phase.

  3. Retardation factor - Wikipedia

    en.wikipedia.org/wiki/Retardation_factor

    In chromatography, the retardation factor (R) is the fraction of an analyte in the mobile phase of a chromatographic system. [1] In planar chromatography in particular, the retardation factor R F is defined as the ratio of the distance traveled by the center of a spot to the distance traveled by the solvent front. [2]

  4. Chromatography - Wikipedia

    en.wikipedia.org/wiki/Chromatography

    Paper chromatography is a technique that involves placing a small dot or line of sample solution onto a strip of chromatography paper. The paper is placed in a container with a shallow layer of solvent and sealed. As the solvent rises through the paper, it meets the sample mixture, which starts to travel up the paper with the solvent.

  5. Elution - Wikipedia

    en.wikipedia.org/wiki/Elution

    Elution principle of column chromatography. In analytical and organic chemistry, elution is the process of extracting one material from another by washing with a solvent: washing of loaded ion-exchange resins to remove captured ions, or eluting proteins or other biopolymers from a gel electrophoresis or chromatography column.

  6. False positives and false negatives - Wikipedia

    en.wikipedia.org/wiki/False_positives_and_false...

    Because of the ambiguity of notation in this field, it is essential to look at the definition in every paper. The hazards of reliance on p -values was emphasized in Colquhoun (2017) [ 2 ] by pointing out that even an observation of p = 0.001 was not necessarily strong evidence against the null hypothesis.

  7. Resolution (chromatography) - Wikipedia

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

    Chromatographic peak resolution is given by = + where t R is the retention time and w b is the peak width at baseline. The bigger the time-difference and/or the smaller the bandwidths, the better the resolution of the compounds.

  8. Two-dimensional chromatography - Wikipedia

    en.wikipedia.org/wiki/Two-dimensional_chromatography

    Gas chromatography-mass spectrometry (GC-MS) is a two-dimensional chromatography technique that combines the separation technique of gas chromatography with the identification technique of mass spectrometry. GC-MS is the single most important analytical tool for the analysis of volatile and semi-volatile organic compounds in complex mixtures. [7]

  9. Standard addition - Wikipedia

    en.wikipedia.org/wiki/Standard_addition

    When working with limiting amount of sample, an analyst might need to make a single addition, but it is generally considered a best practice to make at least two additions whenever possible. [5] Note that this is not limited to liquid samples. In atomic absorption spectroscopy, for example, standard additions are often used with solid as the ...