Separating Substances
By
Mr. A. Rogan
Separating Substances
• When substances are
separated from mixtures
they are said to be
purified or refined
Separating Substances
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Separating Mixtures:
Decanting
Filtration
Evaporation
Distillation
Paper Chromatography
Separating Substances
• Decanting:
• This is a method of separating
an insoluble solid from a liquid.
It is carried out by allowing the
solid to settle and then pouring
off the liquid.
Separating Substances
• Filtration:
• This is a method of separating
an insoluble solid from a liquid
using a material that allows the
liquid to pass through but not
the solid.
Separating Substances
• Mandatory Experiment
18.1: Pg. 199
• To Separate A Mixture Of
Water And Soil Using
Filtration.
Separating Substances
• The solid remaining on the
filter paper is known as
residue.
• The clear liquid which passes
through the filter paper is called
filtrate.
Separating Substances
• Evaporation:
• This involves boiling the solution and
driving the liquid off as steam.
• We are looking for the solid not the
liquid.
• E.g. Separating salt from salt water.
Separating Substances
• Mandatory Experiment
18.2: Pg. 201
• To Separate Sodium
Chloride From A Solution Of
Sodium Chloride In Water
Separating Substances
• Mandatory Experiment
18.3: Pg. 202
• To Purify Rock Salt (Sand
and Salt) using filtration and
evaporation
Separating Substances
• Distillation:
• This is a process involving the
vaporisation of a liquid by
boiling it and then condensing
the vapour by cooling it.
Separating Substances
• Mandatory Experiment
18.4: Pg. 204
• To Obtain A Sample Of
Pure Water From Sea
Water
Separating Substances
• Paper Chromatography:
• This is a technique to separate mixtures
of substances in solution. The solvent
in which the substances are dissolved
is passed along a length of paper and
the dissolved substances separate out
on the paper.
Separating Substances
• Mandatory Experiment
18.5: Pg. 208
• To Separate The Dyes In
A Sample Of Ink Using
Chromatography.