|
==>> For more on Mixtures
(Solutions, Suspensions, Emulsions, Colloids
)
|
| | Solution |
Suspension |
Colloid |
| Appearance |
Clear,
transparent and homogeneous
| Cloudy,
heterogeneous, at least two substances visible | Cloudy
but uniform and homogeneous | | Particle
Size | molecule
in size | larger
than 10,000 Angstroms | 10-1000
Angstroms | Effect
of Light
Tyndall Effect
| none
-- light passes through, particles do not reflect light | variable
| light
is dispersed by colloidal particles | | | Effect
of Sedimentation | none | particles
will eventually
settle out | none |
|---|
In
summary: A
solution is always transparent, light passes through with no scattering
from solute particles which are molecule in size. The solution is homogeneous
and does not settle out. A solution cannot be filtered but can be separated using
the process of distillation. A
suspension is cloudy and heterogeneous. The particles are larger than 10,000
Angstroms which allows them to be filtered. If a suspension is allowed to stand
the particles will separate out. A
colloid is intermediate between a solution and a suspension. While a suspension
will separate out a colloid will not. Colloids can be distinguished from solutions
using the Tyndall effect. Light passing through a colloidal dispersion, such as
smoky or foggy air, will be reflected by the larger particles and the light beam
will be visible. |
