water is more polar than acetonitrile.but in reverse phase chromatography peaks elute earlier when we increse Acetonitrile.what is the reason.

Answer Posted / pankaj rabadia

As per the Vandemeter equition as the viscosity of mobile phase is decreased then mass transfer of the solute will incresed, and it will move faster in column n eluted faster... water is more polar than ACN.. but viscocity of ACN is much lower than Water..So eluting strenth of ACN is higer than Water.

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