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Appendix A: Derivation of k’ for Neutral Compounds

  • Page ID
    63540
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    \[k' = \dfrac{moles_{micelle}}{moles_{aqueous}} \tag{equation 3.1}\]

    \[υ_{apparent} = υ_{eof} \dfrac{η_{aqueous}}{η_{micelle} + η_{aqueous}} + υ_{micelle} \dfrac{η_{micelle}}{η_{micelle} + η_{aqueous}} \tag{equation 3.2}\]

    substitute equation 3.1

    \[υ_{apparent} = υ_{eof}\dfrac{1}{1 + k'} + υ_{micelle}\dfrac{k'}{1 + k'}\tag{equation 3.3}\]

    Given that velocity is the arrival time at the capillary window

    \[υ_{apparent} = \dfrac{l}{t_R} \tag{equation 3.4a}\]

    \[υ_{eof} = \dfrac{l}{t_{eof}} \tag{equation 3.4b}\]

    \[υ_{micelle} = \dfrac{l}{t_{micelle}} \tag{equation 3.4c}\]

    substitute equations 3.4a-c

    \[\dfrac{l}{t_R} = \dfrac{l}{t_{eof}} ( \dfrac{1}{1 + k'} ) + \dfrac{l}{t_{micelle}} ( \dfrac{k'}{1 + k'} ) \tag{equation 3.5}\]

    \[\dfrac{1}{t_R} = \dfrac{1}{t_{eof}} ( \dfrac{1}{1 + k'} ) + \dfrac{1}{t_{micelle}} ( \dfrac{k'}{1 + k'} ) \tag{equation 3.5a}\]

    \[\dfrac{1 + k'}{k' t_R} = (\dfrac{1 + k'}{k'} )[\dfrac{1}{t_{eof}} ( \dfrac{1}{1 + k'} ) + \dfrac{1}{t_{micelle}}( \dfrac{k'}{1 + k'} )] \tag{equation 3.6}\]

    \[\dfrac{1 + k'}{k' t_R} = \dfrac{1}{k' t_{eof}} + \dfrac{1}{t_{micelle}} \tag{equation 3.7}\]

    \[\dfrac{1 + k'}{k' t_R} − \dfrac{1}{k' t_{eof}} = \dfrac{1}{t_{micelle}} \tag{equation 3.8}\]

    \[\dfrac{1 + k'}{k' t_R} − \dfrac{(\dfrac{t_R}{t_{eof}})}{k' t_R} = \dfrac{1}{t_{micelle}} \tag{equation 3.9}\]

    \[\dfrac{1}{k' t_R} (1 + k − \dfrac{t_R}{t_{eof}}) = \dfrac{1}{t_{micelle}}\tag{equation 3.10}\]

    \[(1 + k' − \dfrac{t_R}{t_{eof}}) = \dfrac{k' t_R}{t_{micelle}} \tag{equation 3.11}\]

    \[k' − \dfrac{k' t_R}{t_{micelle}} = \dfrac{t_R}{t_{eof}} − 1 \tag{equation 3.12}\]

    \[k' (1 − \dfrac{t_R}{t_{micelle}}) = \dfrac{1}{t_{eof}} (t_R − t_{eof}) \tag{equation 3.13}\]

    \[k' = \dfrac{(t_R − t_{eof})}{t_{eof} (1 − \dfrac{t_R}{t_{micelle}})} \tag{equation 3.14}\]


    This page titled Appendix A: Derivation of k’ for Neutral Compounds is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Contributor.

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