For 10 points, name this movement of molecules from high concentration to low concentration.
The capillary and diaphragm techniques measure a constant quantifying this process, and for low Reynolds number, that constant equals Boltzmann's constant times temperature over six pi times viscosity times particle radius. This phenomenon is used to introduce interstitial defects into crystals, such as carbon substitution for steel. This process controls the (*) rate of catalytic reactions with very high turnover numbers. A gradient of chemical potential is the thermodynamic driving force for this process. This process occurs through random walk in Brownian motion, and when it occurs through a semipermeable membrane, it's called osmosis. For 10 points, name this movement of molecules from high concentration to low concentration.
The capillary and diaphragm techniques measure a constant quantifying this process, and for low Reynolds number, that constant equals Boltzmann's constant times temperature over six pi times viscosity times particle radius.
diffusion [prompt on osmosis before it is read]