chm presentation
TRANSCRIPT
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GROUP MEMBERS:
- Muhammad Aizuddin Bin Khalid- Muhammad Noorfaez Bin Azaini
- Nurazliyana Binti Mat Radzi
CLASS: DS3F1
LYOPHILIC AND LYOPHOBIC SOLUTION
(STABILITY OF LYOPHOBIC SOLUTION ANDPROPERTIES)
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DEFINATION OF LYOPHILIC SOLUTION
Characterized by strong attraction betweenthe colloid medium and the dispersionmedium of a colloidal system.
The disperse phase is relatively liquid,usually comprising highly complex organicsubstances such as starch, which readilyabsorb solvent, swell, and distributeuniformly through the medium.
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DEFINATION OF LYOPHOBIC SOLUTION
An unstable colloid system in which
the disperse phase particles tend to
repel liquids, are easily precipitated,and cannot be redispersed withadditional solvent.
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PROPERTIES OF LYOPHILIC SOLUTION
Lyophilic colloids are liquid loving colloids
Lyo means solventand philic meansloving.
DEFINITION
Sols of organic substances like gelatin,gum, starch and proteins.
EXAMPLES
Easy to prepare. It can be prepared directly by mixing
colloid with liquid. Additional stabilizersare not required during their preparation.
EASE OFPREPARATION
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It relatively stable as strong forces ofinteraction exist between colloidalparticles and liquid.
STABILITY
It depends upon pH. It can be negative, positive or
neutral.CHARGE
It higher viscosity than that of themedium.VISCOSITY
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It reversibility.
This is because on evaporating theliquid, the residue left will passes
into colloidal state on addition ofliquid.
REVERSIBILITY
It is less than that of dispersionmedium.
SURFACE TENSION
It depend on the nature of chargethese particles may migrate tocathode or anode or may not move at
all.
ELECTROPHORESIS
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PROPERTIES OF LYOPHOBIC SOLUTION
DEFINITION
Lyophobic colloids are liquid hating colloids.
Lyo means solventand phobic means hating.
EXAMPLES
Sols of inorganic substances like Arsenic(As2S3), Iron (Fe(OH)3) and Platinum.
EASE OFPREPARATION
It easy to prepare.
It cannot be be prepared directly by mixingcolloid with liquid.
Special methods are employed to preparelyophobic sols and additional stabilizers arerequired during their preparation.
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STABILITY
It less stable as weak forces of interaction existbetween colloidal particles and liquid.
CHARGE
It can be positive or negative.
As2S3 sol is negative in nature while Fe(OH)3 sol ispositive in nature.
VISCOSITY
It have almost same viscosity as that of medium.
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REVERSIBILITY
It is irreversible. This is because on evaporating the liquid, the
residue left cannot be converted intosolution on mere addition of liquid
SurfaceTension
The surface tension is nearly same as that ofdispersion medium.
ELECTROPHORESIS
It dependon the nature of charge these particles
migrate to either cathode or anode.
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ANY QUESTION?