Most diffusible ion across membrane -

Ans. is 'c' i.e., Cl?Among the given options, Cl- has lowest permeability coefficient and maximum permeability.Permeability of membraneAs the major middle poion of membrane (core of the membrane) is formed by hydrophobic region of phospholipids, this poion is impermeable to the usual water-soluble substances, such as ions, glucose and urea. Conversely, fat-soluble substances, such as oxygen, carbon dioxide, and alcohol, can penetrate this poion of the membrane with ease.The permeability coefficients of small molecules in the lipid bilayer correlate with their solubilities in nonpolar (hydrophobic) region and thus their permeability.