Calculator

Diffusivity, Stokes-Einstein equation

With the Stokes-Einstein equation you can calculate the diffusivity, the temperature, the radius and the viscosity.

D = kB × T 6π× η × r
() [m² s⁻¹] = kB × () [K] 6π× () [Pa s] × () [m]

To fill in a variable, click on a bracket "()", a variable or a unit.
Input a number or a calculation, choose a unit and click on the button "Insert input".
The variable that you want to calculate, should be empty or filled in with an "x"/"X".
If everything is filled in correctly, a button ("Calculate") shoud appear, that has to be pressed.

If the calculation duration is too long (over 10 seconds) or an error occurs, check if every variable is filled in correctly.

Variables

D Diffusivity
kB Boltzmann constant = 1.38064852·10-23 [kg m2 s-2 K⁻¹]
T Temperature
η Dynamic viscosity
r Radius
{solns = solve([}
{(}
{()}
{*}
{1}
{)}
{==}
{(}
{(}
{1.38064852*10**-23}
{*}
{1}
{)}
{*}
{(((}
{()}
{+}
{0))}
{)}
{)}
{/}
{(}
{6}
{*}
{3.141592653589793}
{*}
{(}
{()}
{*}
{1}
{)}
{*}
{(}
{()}
{*}
{1}
{)}
{)}
{}