Suspension Colloidal solution True solution Particle size
$>\, 100\, nm$ $\,$ $1\, nm-100 \, nm$ $\,$ $<\, 1\, nm$
Colloidal solution is a heterogeneous solution which contains particles of intermediate size.
The particles of a colloidal solution have diameters between $1$ to $100 \,nm$. Colloidal solution shows the optical property (i.e., Tyndall effect and Brownian movement)