cm²/s
square centimeter per second
Diffusivityexact by definition
The square centimetre per second is exactly 10⁻⁴ m²/s, which is identical to the CGS unit called the stokes. It is the traditional unit for mass diffusion coefficients in chemistry, where gas-phase diffusivities are around 0.1 cm²/s and liquid-phase ones around 10⁻⁵ cm²/s. The factor is exact by definition.
| 1 cm²/s | 100 mm²/s |
Where the unit came from
The stokes is named for George Gabriel Stokes, whose work on viscous flow produced the drag law and the equations that carry his name. One stokes is one square centimetre per second, and its hundredth, the centistoke, is what lubricant grading actually uses.
Solvers that use diffusivity