Colloidal solution show tyndall effect but true solution do not explain

Scattering of light through a solution when light passes through it is called Tyndall effect.

In a colloidal solution, the particle size is between 1 nm to 100 nm, when light rays fall on colloidal solution, these particles sizes allow scattering of light ray.

But in true solution the size of particles is smaller than 1nm and unable to scatter the light and do not show tyndall effect.

Hence, colloidal solution shows tyndall effect but true solution do not.

a pan containing water is placed in a positio n where it is exposed to a 10 mile per hour wind. the pan contains a uniform depth of 1.27 cm of water, is quite wide, and has a length of 2.44 m in the wind direction. the water in the pan is at a constant temperature of 15.5 °c.

the formula mass of a molecule or a compound is the sum of the atomic weights of the atoms in its empirical formula

(that's what i know about formula mass)