Solutions And Crystalisation Flashcards
What is the solvent
Solvent: the liquid the solute is dissolving in.
Define solution and give examples
Solution: the solute and the solvent.
Coffee granules and water.
Milk and hot chocolate powder
Air in a sugar paste=marshmallow
What is the solute
Solute: the substance being dissolved.
What is a saturated solution
A solution that contains as much dissolved solute as possible at that temperature
Explain soluble
If a substance dissolves in the solvent it is soluble
Explain insoluble
If a substance does not dissolve in a substance it is know as insoluble
What is the solubility of a substance
How much it can dissolve
What does solubility depend on
The temperature of the solvent and the volume of the solvent
Explain crystallisation
The formation of crystals by cooling a saturated solution
Explain a dilute solution
A solution that doesn’t have much solute and a lot of solvent
Explain a concentrated solution
A solution that contains a lot of solute and little solvent
Explain the experiment to grow crystals with copper sulphate
- Add water to a beaker until it’s half full and heat on the hot plate.
- Slowly and with constant stirring, add the copper sulfate to the water.
- Heat the water to 70°C and add in more copper sulfate until no more will dissolve.
- Pour approximately half of the solution into a pre-warmed evaporating dish and allow to cool slowly.
- The remaining solution in the beaker can be quickly cooled by standing it in iced water or by allowing running water from the tap to pour over the outside of the beaker.
What is the result and conclusion of the experiment: to grow crystals using copper sulphate
Result
The different cooling methods result in different sized crystals.
Conclusion
Crystallisation occurs when a hot, saturated solution is cooled.
How would you conduct a experiment To investigate the solubility of a variety of substances in water
You would
Gather several substances to be dissolved in water. Ex: salt, pepper, sand.
Half fill a beaker with water and add your first substance.
Stir the solution
Repeat this with other substances
If they dissolve they are soluble and if not they are insoluble