CHAPTER 13: SOLUBILITY Flashcards
solubility definition
Maximum amount of solute that can be dissolved in a given quantity of
solvent (commonly 100g) at a certain temperature
solute, solvent, solution
- solute: substance being dissolved
- solvent: liquid the solute dissolves in
- solution: solute dissolved in liquid
saturated solutions
No more solute can be dissolved at a particular temp
unsaturated solution
More solute can be dissolved at a particular temp
supersaturated solution
- An unstable solution that contains more dissolved solute than a saturated.
- When disturbed, some of the solute will come out of the solution
Super solutions are prepared by heating a solvent, dissolving a LOT of solute and letting it cool slowly.
Adding a ‘seed crystal’ to the supersaturated solution after it has cooled causes the solute to ‘crystallise’ and come out of the solution.
solubility + temp
- the solubility of a substance increases as temperature increases
- This is because at high temp, the solute and solvent have more energy to overcome the forces of attraction that hold the particles together
crystallisation
- Cooling reduces the solubility of a dissolved solute to a point where not all the substance present is soluble
- When an unsaturated solution becomes saturated, crystals form
- Solubility curves can be used to predict how much compound will crystallise out of a solution as temperature decreases
solubility of liquids and gases in water
Dissolving Solids - Solubility increases as temp increases
Dissolving Gases - Solubility decreases as temp increases
Dissolving Liquids - No clear trend in solubility as temp increases
concentration units
- have two parts
- first part gives info on amount of solute
- second part gives info on the amount of solution