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Tuesday March 22 , 2011. (Solubility). Bell Ringer Tuesday, 3-22-11. What is occurring at the molecular level when no more solute will dissolve in a certain amount of solvent at a given temperature?. Bell Ringer Tuesday, 3-22-11.
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TuesdayMarch 22, 2011 (Solubility)
Bell RingerTuesday, 3-22-11 What is occurring at the molecular level when no more solute will dissolve in a certain amount of solvent at a given temperature?
Bell RingerTuesday, 3-22-11 The number of molecules leaving crystals of the solute equals the number of molecules returning and sticking to the crystals.dissolution = crystallization
CompleteWorksheet Solubility
Solubility • If more water is added to the saturated solution, then more sodium chloride will dissolve in it. • At 20°C, 35.9 g of NaCl is the maximum amount that will dissolve in 100 mL of water. • A solution that contains less solute than a saturated solution under the existing conditions is an unsaturated solution.
Solubility • When a saturated solution of a solute whose solubility increases with temperature is cooled, the excess solute usually comes out of solution, leaving the solution saturated at the lower temperature. • But sometimes, if the solution is left to cool undisturbed, the excess solute does not separate and a supersaturated solution is produced.
Solubility • A supersaturated solution is a solution that contains more dissolved solute than a saturated solution contains under the same conditions. • A supersaturated solution may remain unchanged for a long time if it is not disturbed, but once crystals begin to form, the process continues until equilibrium is reestablished at the lower temperature.
Solubility • The solubility of a substance is the amount of that substance required to form a saturated solution with a specific amount of solvent at a specified temperature. • Ex) the solubility of sugar is 204 g/100 g of water (at 20.°C.) • The temperature must be specified because solubility varies with temperature. • For gases, the pressure must also be specified.
Solubility • Solubility values can be found in chemical handbooks and are usually given as grams of solute per 100. g of solvent or per 100. mL of solvent at a given temperature. • The rate at which a solid dissolves is unrelated to solubility - the maximum amount of solute that dissolves and reaches equilibrium is always the same under the same conditions.