The un-ionized form is usually lipid soluble (lipophilic) and diffuses readily across cell membranes. The ionized form has low lipid solubility (but high water solubility-ie, hydrophilic) and high electrical resistance and thus cannot penetrate cell membranes easily.
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Sir how ionisation affect diffusion
The un-ionized form is usually lipid soluble (lipophilic) and diffuses readily across cell membranes. The ionized form has low lipid solubility (but high water solubility-ie, hydrophilic) and high electrical resistance and thus cannot penetrate cell membranes easily.