Question

Which of the following statement is incorrect Select one: a. The degree of dissociation of weak electrolyte depends on concentration b. Both A and C are correct c. The degree of dissociation of weak electrolyte increases as concentration increases d. The degree of dissociation of strong electrolyte is 1 at all concentration e. The molar conductivity at infinite dilution cannot be obtained from extrapolation of molar conductivity versus concentration back to zero concentration for weak electrolyte Next page

Answer 1

Degree of Dissociation ($\alpha$) is the amount or fraction of solute that has dissociated (generally in aqueous meedium).

• Strong electrolyte dissociates completely and hence, have $\alpha$ nearly equal to 1.
• Weak electrolytes don't dissociate completely and have $\alpha$ less than 1.
• For weak electrolytes, $\alpha$ = (K_d/C_o)^1/2 , therefore, with increase in concentration, $\alpha$ decreases.
• Molar conductance for weak electrolytes is detemined theoretically as, the graph obtained reaches infinity and can not be extrapolated properly.

Option b. is incorrect as only a. is correct and c. incorrect.