Countercurrent gas centrifuges have been used to separate 235 U from 238 U. The rate of diffusive transport is K= 2Dr.

Countercurrent gas centrifuges have been used to separate 235U from 238U. The rate ofdiffusive transport is K= 2πDρr. If K= rate of transport of light component to thecenter of the centrifuge, in g mol/(s)(cm of height); D= diffusion coefficient; ρ= molardensity, g moles/cm3; and r= log mean radius, (r2– r1)/ln (r2/r1), with rin cm, whatare the units of D?