Why on dilution the `Lambda_(m)` of `CH_(3)COOH` increases drastically, while that of `CH_(3)COONa` increases gradually?

Explanation

`Ch_(3)COOH` is a weak electrolyte and is dissociated to small extent (`alpha` is quite small). With dilution, its degree of dissociation increases i.e. more ions are released in solution. Therefore, `Lambda_(m)` of `CH_(3)COOH` increases drastically. On the other hand , `CH_(3)COONa` is a strong electrolyte and is almost completely and is almost completely dissociated in aqueous solution (`alpha` is nearly one). With dilution, only interionic forces of attraction increase resulting in only small increase in the value of `Lambda_(m)`. For more details, consult section 3.19