In Capillary Electrophoresis, for a representative 50 cm capillary column operated at 30,000 V, typical net mobility for a 10 min migration time is about $2\times10^{-8}\ \text{m}^2\text{s}^{-1}\text{V}^{-1}$. Calculate the number of theoretical plates for an ion having diffusion coefficient $D = 1\times10^{-9}\ \text{m}^2\text{s}^{-1}$.