Potassium ferrocyanide is 50% ionized in aqueous
solution, its van't Hoff factor will be equal to ——.

K4[Fe(CN)6]•3H2O => 4K⁺ + [Fe(CN)₆]^4-

1                               0             0                          (initial)

1-x                            4x          x                         (atfter dissociation)

vant hoff factor (i) = moles after dissotion/total initial moles

                          = 1+4x

50% ionise means x = 0.5 so

 i = 1 + 4*0.5 = 3

its vant hoff factor is 3