The Van Deemter equation notes

The Van Deemter equation notes - diffusion. C depends on...

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The Van Deemter equation is an equation that describes the dependence of  chromatographic plate height on linear flow rate.  H  represents plate height, and u x  represents  linear flow rate. The Van Deemter equation is:  A  +  B /u x  +  C u x Column band broadening originates from three main sources: multiple path of an analytie  through the column packing, molecular diffusion, and effect of mass transfer between phases. In  the above equation, A, B, and C are all constants. A depends on band broadening processes,  such as multiple flow paths, that are independent of flow rate. B depends on the rate of molecular 
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Unformatted text preview: diffusion. C depends on rate of mass transfer between the stationary and mobile phases. In problem 2-25, A was 1.65mm, B was 25.8 mmmL/min, and C was 0.0236 mmmin/mL. The smaller the value of B, the larger the H value got, and vice versa. . The larger the value of C, the larger the H value got, and vice versa. The smaller the plate height, the narrower the band, and vice versa....
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This note was uploaded on 09/27/2010 for the course CHEM 393 taught by Professor Anderson during the Spring '04 term at Ramapo.

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