[Thet619]

Hi,
how can I calculate the amount of resin I need (e.g. DOWEX50WX4 with a total exchange capactity of 1.1 meq/ml) if I want to convert 1mmol of NaCl into its acid?

Thanks

[Babcock_Hall]

Others here may have a more sophisticated approach, but I often aim for a large excess, about twentyfold, when estimating how much resin to use.  Another consideration is the relative affinities of the resin for the two ions in question.  IIRC sodium binds slightly more strongly than protons, but you should double-check this.