The value of van't Hoff factor of the given molecule is as follows :
Al2(SO4)3 K2SO4 K3[Fe(CN)6]Al(NO3)3⇌2Al3++3SO42−,i=5⇌2 K++SO42−,i=3⇌3 K++[Fe(CN)6]3+,i=4⇌Al3++3NO3−,i=4
The van't Hoff factor for
K4[Fe(CN)6] is
K4\left[\mathrm{Fe}(\mathrm{CN})_6\right] \rightleftharpoons 4 \mathrm{~K}^{+}+
[Fe(CN)6]4−,i=5
∴Al2(SO4)3 has the same value of van't Hoff factor as that of
K4[Fe(CN)6].