Koloid and Its Properties

Post on 18-Nov-2014

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KOLOID AND ITS PROPERTIES

By :Ika Farida Yuliana ( 093194007 )Noor Fathi Maratusholihah (093194022)Yudit Yulianinda (0931940 )

Definition

•Colloid is a “ metastable” mixture system ( as though in stable condition, but it will separate after a certain time)

•Colloid different with the solution stable•Generally, there are 2 substance in colloid :

- Dispersed substance dissolved substance in colloid - Disperser substance solvent in colloid

Dispersed Phase Disperser Name Example

Gas Gas Not colloid, gas mix homogenously

Gas Liquid Foam Wave, soap

Gas Solid Compact foam Foam bed

Liquid Gas Liquid aerosol Fog, hair spray

Liquid Liquid Emulsion Milk, mayonnaise

Liquid Solid Gel Butter

Solid Gas Compact aerosol

Spot

Solid Liquid Sol Tint , paint

Solid Solid Compact solid Sand , glass

Colloids based on its dispersed and disperser

phase :

Colloid Properties

Tyndall effect

Liofil and

LiofobCoagulatio

n

Colloid charge

Brown motion

Adsorption

Purification

Stability

Emulation

1. Tyndall effect•Tyndall effect is light dispersal by colloid solution, an instance where the way of light in colloid can be seen because colloid particle can scatter light to all direction.

•Example: sunshine that scattered colloid particle at sky, up to blue colored sky in the day time and pink in the evening; dust in room will be seen if there incident ray passes gap.

• True solution (left picture) is illuminated with light, not scatter light,

• Colloid system (right picture) light scattered.

2.Brownian Motion

•Particles movement can has random like in hydrogen and gas, or only vibrate in place like in solid substance.

•Collision go on from all direction . Because particle size enough little, so collision that inclined uneven.

•So that found a collision resultant that causes particle movement direction change so that happen movement zigzag or Brownian movement.

# Brownian motion factor :•Smaller the size of particle, faster the

Brownian motion difficult to be seen•Higher temperature , faster Brownian

motion

3. Adsorption•Adsorption is absorption of substance or

ion on colloid surface. character adsorption used in course of: 1. cana sugar purifying. 2. norit. 3. water depurating.

•Example: colloid between diarrhea

medicine and liquid in intestines that will absorb diarrhea cause germ.

•colloid Fe(oh)3 will adsorb H+ so that will be to contain +.

•colloid As2S3 adsorb OH- ion in solution so that will contain -

4. Colloid Charge •Have same type of charge give stability

to system•Determined by ion charge absorbed by

colloid surface•Can move in electric field•example: factory chimney set metal plate

that contain electricity as a mean to crumpling the dust.

5. Coagulation•Coagulation colloid is colloid clotting

because electrolyte the load contrary to. •example: dirt in water that crumpling by

alum so that water is clear. • factors that causes coagulation: • temperature change. • informer. • increasing ion with big load (example:

alum). • positive colloid mixing and negative

colloid.

6. Liofil and liofob colloid•Happen in sol condition• Liofil ( like water ) adsorb the liquid ,

so it forms cover around the colloid- Dispersed phase’s affinity > disperser media- Example : starch sol, jelly , glue

•Liofob ( dislike water ) not adsorb the liquid

- dispersed phase’s affinity < disperser media - Example : Sulfur sol , golden sol

7.Emulasion•Emulasion is liquid colloid in liquid

medium. so that solution kolid stable, into colloid usually added emulsifier, that is substance penyetabil so that stable colloid.

•example: milk is underwater fat emulsion with kasein as emulsifier.

8.Colloid stability

a. many colloids that must be defended in the form of colloid to its use.

• example: ice-cream, ink, paint. • for that be used colloid other that can form

layer at around colloid. colloid other this called patron colloid.

• example: gelatine in sol fe(oh)3. b. for colloid shaped emulsion can be used

emulgator that is substance that can interested in second liquid that form emulsion

• example: detergent soap as emulgator from oil emulsion and water.

9. Purification of Colloids

•By cleaning the disturbing ions dialysis•It will be faster if the electric current is

added electro dialysis

Thank You