Diffusive Constant

#Physics

$\displaystyle D=\frac{\delta ^{2}}{2\tau}$

  • Diffusive constant
  • Essentially tells you how quickly something diffuses
  • $\displaystyle \tau$ is the time per step
  • Has units of $\displaystyle \mathrm{\frac{m^{2}}{s}}$
Molecule$\displaystyle D$ in $\displaystyle \ce{H_{2}O}$ at $\displaystyle 25^\circ \mathrm{C,(cm^{2}/s)}$
$\displaystyle \ce{CO_{2}}$$\displaystyle 1.9\cdot 10^{-5}$
$\displaystyle \ce{O_{2}}$$\displaystyle 2.1\cdot 10^{-5}$
Protein$\displaystyle 10^{-6}$
Protein in lipid$\displaystyle 10^{-8}$
Protein in cell$\displaystyle 10^{-7}$