How can we help?

You can also find more resources in our Help Center.

39 terms

Hydrophilic vs Hydrophobic Colloids

STUDY
PLAY
Hydrophilic colloids have a
high viscosity
The high viscosity associated with the hydrophilic colloids allow you to
interact the dispersion phase with the dispersion medium
The hydrophobic colloids have a
low viscosity
The low viscosity associated wit the hydrophobic colloids prevent the
dispersion phase from interacting with the dispersion medium
The hydrophilic colloid haS a
difficult time passing light through the colloid
- it has a low Tyndall Effect
The hydrophobic colloid
does not have a difficult time passing light through a colloid
The hydrophilic colloids are
very stable
they are not reactive to a low concentration of electrolytes
The hydrophobic colloids are
very unstable
they are very sensitive to a low concentration of electrolytes
Can hydrophilic colloids be reversed
Yes they are reversible
If you take a hydrophilic colloid heat it, get rid of the water and then place it back into water it
can be reused again
The hydrophobic colloids are
irreversible and you can not use them again after they have been used
The materials in which the hydrophilic colloids are dispersed in are
organic and inorganic
The molecules that the hydrophobic colloids are dispersed in are
inorganic material
what type of charge is associate with the hydrophobic colloids
positive or negative
What type of charge is associated with the hydrophilic colloids
positive, negative and neutral
How are hydrophilic colloids created
by mixing the colloid in water, there is no special procedure required
How are hydrophobic colloids created
via chemical or physical means
- mortal and pestle via grinding into smaller pieces
Hydrophilic colloids become
ionized when place in water
Hydrophobic colloids do
not ionize when placed in water but they become charged by picking up ions from the dispersion medium during preparation
Hydrophobic colloids can be prepared physically by
grinding up the substance with a mortal and pestle and then adding them to the dispersion medium
Methods used to prepare a hydrophobic colloid include
colloid mill
micronizer
ball mill
ultrasonic generator
When preparing a hydrophobic colloid you have to manipulate the particle size by getting it into
colloïdal range by changing the solvent
- this is known as the condensation method
Manipulation of the size of colloid sulfur occurs by adding sulfur to hot alcohol to produce
sulfur in the sub colloidal range
at this point the substance is insoluble in water and it will precipitate our
Once the colloidal sulfur has been precipitated out its in
colloïdal range
- it then has charges that will allow it to be kept in suspension
AgNO₃+ NaCLl→AgCl+ NaCo₃ is an example of
condensation with a chemical reaction
A high concentration of NaCl with a low concentration of AgNO₃ the particle will be
negative charged
A low concentration of NaCl with a high concentration of AgNO₃ the particle will be
positively charged
Schulze- Hardy has a rule pertaining to
hydrophobic colloids
Hardy states that the
arrangement od the ions should be based upon their ability to precipitate hydrophobic colloids related to the value of the compound
Trivalent compounds will have a greater precipitate power than
monovalent compounds
AlCl+++ takes
less AlCl to PPt in the hydrophobic colloid and is more sensitive to electrolytes
NaCl+ has the
lowest precipitate port and it take more NaCl to ppt in the hydrophobic colloid
less sensitive to electrolytes
If you treat a hydrophobic colloid with a hydrophilic colloid (protective) the hydrophobic colloid
will not respond to the change in e-
Hydrophilic colloids are not
affected by charge
As it relates to charge the hydrophobic colloids
are affected
Hydrophilic colloids have a
↑ attraction for the dispersion medium
Hydrophobic colloids have a
↓ attraction for the dispersion medium
As it relates to stability hydrophilic colloids are
stable to a low concentration of electrolytes
As it relates to stability hydrophobic colloids are
not stable to a low concentration of electrolytes