What do these have in
common?
Red Wine
Salt Water
Crude Oil
Toilet Waste
What does this group have in
common?
Coffee
Gold
Gas
Drinking
Water
What connects the two groups?
VS
Impure
 Separation of Mixtures 
Pure
Separation of Mixtures
Separation
Techniques:
Homogeneous
and
Heterogeneous
Mixtures
Techniques
•
•
•
•
•
•
•
Decantation
Sedimentation
Filtration
Centrifugation
Distillation – Simple and Fractional
Magnetism
Chromatography
Decantation
The only equipment needed is a container:
you can use a beaker.
In decantations, the suspended particles
settle to the bottom of the container. The
separation obtained is sometimes partial,
because there are still some particles
suspension
Sedimentation
• By giving a mixture time to sit, you allow
heavier particles to settle at the bottom
• You can then skim off the pure liquid from
the top or pour it out
• Good for separating large particles from
liquid mixtures where you don’t need to
get 100% of them.
• Cheap
• E.g. Toilet Wastewater.
Filtration
• FILTRATION: is a method that allows a good
separation of the liquid phase (the filtrate which
passes through the paper - filter) from a solid
phase (the residue that remains on paper - filter)
• Filtration rate depends on:
characteristics of the material - filter (the quality
of equipment - filter, the filter area, pore size
etc..)
• Equipment - filter can be: paper - filter (most
often), the porous glass, textile material
Centrifugation
• The mixture is poured into containers that
are put in rotation around a fixed axis: as a
result of centrifugal force, the heavier
particles are expelled into the bottom of
the container. This technique is used when
the mixture contains solid particles so
small that settling is impossible or too long
(as in the dairy industry or laboratories).
Simple Distillation
• Distillation is the process of heating a
mixture of liquids until they boil, at
different temperatures, capturing and
cooling the resultant hot vapors, and
collecting the condensed vapors
(liquid is condensed into flask).
Fractional Distillation
Fractional Distillation
• A process by which components in a chemical
mixture are separated according to their different
boiling points. Vapors from a boiling solution are
passed along a column. Components with a
higher boiling points condense on the column
and return to the solution; components with a
lower boiling points pass through the column
and are collected.
Examples: Gasoline is produced from crude oil
using fractional distillation.
Magnetism
• Magnetic separation is a process of
sorting that uses the magnetic properties
of a portion of a mixture of solids.
Magnetic separators are often used in the
treatment of coal and mineral ores. In
simple mixtures, a magnet is used to pull
all magnetic materials away from the core
of the mixture.
Chromatography
• Chromatography is a method for analyzing
complex mixtures (such as ink) by
separating them into the chemicals from
which they are made. Chromatography is
used to separate and identify all sorts of
substances in police work. Drugs from
narcotics to aspirin can be identified in
urine and blood samples, often with the
aid of chromatography.
• Because molecules in ink and other
mixtures have different characteristics
(such as size and solubility), they travel at
different speeds when pulled along a piece
of paper by a solvent (in this case, water).
• HW: page 201 # 1-5