Calculate the percent dissociation of 0.02 m solution if its freezing point depression is 0.046 K [ K _ f . for water .=1.86 ~K ~kg ~mol ⁻¹ ; n =2 ]

Step-by-step solution

The percent dissociation is determined using freezing point depression data. The van't Hoff factor i is calculated as i = T_f K_f m = 0.046 1.86 0.02 1.23656 . For a substance dissociating into two ions, i = 1 + (2 - 1) . Substituting gives 1.23656 = 1 + , so 0.23656 . The percent dissociation is therefore 0.23656 100 % 23.656 % , which rounds to 23.7 % . The closest option is B .