Dissolution is the process by which a solid enters into solution.
In 1897 Noyes and Whitney came up with: “The rate of solution of
solid substances in their own solution.”
dc / dt = K (Cs-Ct)
According to their research, rate of dissolution of solid substances is determined by rate of diffusion of a very thin layer of saturated solution that forms instantaneously around the solid particle. They developed the mathematical relationship that correlates the dissolution rate to the solubility gradient of the solid.
Diffusion layer model / film theory
In 1904, Nerst and Brunner applied Fick’s law of diffusion to the
Noyes-Whitney equation. (Diffusion layer model / film theory)
dc / dt = K D.S / v.h (Cs-Ct)
Cube root law of dissolution
In 1931, Hixson and Crowell came up with Cube root law of
W01/3-W1/3 = Kt
Scheme of dissolution
Later Wagner followed by Carstensen gave the scheme of dissolution.
Initial mechanical lag
Wetting of the …
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