Mixture & Compound.Alloy.Separation Techniques 1 21/1/13

Revision: Element, Compound & Mixture

Example of a mixture of elements

Example of a mixture of compounds

Alloy:

• MIXTURE
• Mixture of metals with other elements
• Stronger. Not malleable

* STEEL

   STAINLESS STEEL

   BRONZE

   COPPER   MUST KNOW-S!

Separation Techniques

• Used only for Mixture
• Physical Means

1.          Magnetic Attraction
2.          Filtration
3.          Use of separatin funnel
4.          Distillation
5.          Crystallization
6.          Evaporation
7.          Sublimation

Method used depends on element's properties. e.g. soluble/insoluble

Mixture needs to be separated into pure substance for...

• Characterization (identify properties)
• Identification ^
• Production of useful substances such as medicine

Paper Chromatography

• separate a mixture of solutes with different solubility and degree of absorption
• The method uses a solvent moving over a porous or absorbent medium

Solvent : Water / ethanol

Principle ( Uncompleted)

• As solvent travels up the paper, the dyes dissolved
• some dyes are more soluble, so they travel faster up the paper
• dyes that are less soluble remain as the bottom of the paper (own comment)

example of a paper chromatography experiment