Solubility
•  The solubility of a substance refers to the maximum amount of that
substance(solute) that can be dissolved in a given quantity of
solvent at a certain temperature.
•  A solution in which no more solute can be dissolved at that
temperature is described as a saturated solution.
•  The measure of solubility of a substance at a given temperature is
how many grams dissolve in each 100 g of solvent to form a
saturated solution.
•  The units of solubility are written as g/100 g solvent.
But first lets convert some units… ÷1000
Volume Number of μL ×1000
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1. 3.68 kg = __________ g 2. 568 t = __________ g 3. 8700 ml = __________ l 4. 25 mg = __________ g 5. 0.101 l = __________ μl 6. 250 ml = __________ l 7. 600 g = __________ kg 8. 8900 kg = __________ μg 9. 0.000004 kl = __________ ml 10. 0.250 kg = __________ mg • 
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1. 3680g 2. 568000000g 3. 8.7L 4. 0.025g 5. 101000μL 6. 0.250L 7. 0.6kg 8. 8900000000000μg 9. 4mL 10. 250000mg Solubility
•  Solubility values allow us to compare the extent to which different
solutes dissolve.
•  Substances such as calcium carbonate, that have very, very small
solubilities, are said to be insoluble.
Solubility Tables
Solubility Curves
•  The relationship between solubility and temperature can be
represented by a solubility curve.
•  Each point on the solubility curve represents a saturated solution - a
solution in which no more solute can be dissolved at the particular
temperature.
•  Any point below a curve represents an unsaturated solution for that
solute.
•  An unsaturated solution contains less solute than is needed to make
a solution saturated at that temperature.
Solubility Curves
Crystallisation
•  Honey often crystallises if you keep it in the refrigerator or if the
weather is very cold.
•  The sugar becomes less soluble as the honey cools.
•  The sugar that will no longer stay dissolved comes out of solution as
crystals in a process known as crystallisation.
•  If a hot saturated solution of potassium nitrate is cooled, crystals of
the solute will appear.
•  This happens because potassium nitrate also becomes less soluble
as the temperature falls.
•  The potassium nitrate crystallises from solution.
Supersaturation
•  A supersaturated solution can be
prepared by slowly cooling a saturated
solution.
•  When this is done, the solution contains
more solute than it should at that
temperature. This is very unstable.
•  The addition of a small crystal seed or
even some dust will cause the excess
solute to crystallise.
Solubility of Gases •  As opposed to solids, gases become less soluble at higher temperatures. You can see this when you boil water. Small bubbles of dissolved gases form when the water is heated and escape into the atmosphere. •  Also, the solubility of gases increases with an increase in pressure. This can be seen when you open up a boRle of soS drink. The carbon dioxide in the solvent stay dissolved as long as they are under pressure. When you decrease the pressure by opening up the boRle the gasses come out of soluVon and escape in a rush of bubbles.