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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?