Transcript ‘impure substances’ •Suspensions •Solutions (mixtures like bore water)

‘impure substances’
(mixtures like bore water)
•Suspensions
•Solutions
- Held together by physical means - not chemically altered.
Experiment = ‘solutions’ of salt + water or sugar + water
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Solutions
•homogeneous mixture
(particles evenly distributed)
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Some common solutions
alcohol and water
salt in water
sugar in water
soft drink
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Solutions
•transparent - so you can see through them.
They may have "colour" but will still be
transparent.
•do not separate on standing.
•have particles so small they cannot be
separated by normal filtration.
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Solvent = the dissolving part of the
solution (eg. water).
Solute: The dissolved part of the solution
is called the solute (eg. salt or sugar)
Solution: A solution is a homogeneous
mixture of solvent and solute particles the
size of ions, atoms, molecules.
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Not only solids in liquids!
gas in gas
gas in liquid
liquid in liquid
solid in liquid
gas in solid
liquid in solid
solid in solid
air ( N2, O2 , Ar, CO2 , other gases)
soft drink (CO2 in water)
petrol (mix of hydrocarbon compounds)
sea water (and other salts in water)
H2 in platinum or palladium
dental amalgams ( mercury in silver)
alloys ( brass, (Cu/Zn), solder (Sn/Pb)
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Suspension
A suspension is a heterogeneous
mixture in which the solute particles
are larger than molecules or ions
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Suspension
•Particles big enough to be seen
by the naked eye.
•Suspensions are "murky" or
"opaque".
•Separate on standing.
•Can be separated by filtration.
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Examples of suspensions
Blood
Sand in water
Soil in water
Chalk in water
Tomato juice
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•When two liquids totally mix
they are called ‘miscible’.
•When two liquids don’t mix
totally they are ‘immiscible’.
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Emulsion
A suspension consisting of two liquids that
do not mix.
Milk (non-homogenised)
Oil in vinegar (french dressing)
Oil in water (Italian dressing)
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