Seperation Techniques Flashcards
Distinguish between mixtures and compounds by identifying their different properties.
Mixture:
Its substances/atoms are not joined together
The substances in the mixture keep their own properties
It is easy to separate
You can change the amount of substances
Compound:
Atoms of its elements are chemically joined together
A compound has different properties to those of its elements
You need to do chemical reactions to split a compound into its elements
The relative amount of each element can not change
Interpret the particle models that show elements, mixtures and compounds
On the photo
Define a ‘solution’ using the terms solute and solvent
A type of mixture where a solute is dissolved into a solvent.
Draw particle diagrams to represent solutions and pure substances
See photo
Explain why temperature affects the amount of solute dissolved in a solution
Most substances get more soluble as temperature increases.
Explain the term ‘solubility’
The mass of solute that dissolves in 100 g of water to make a saturated solution is called the solubility of the solute.
Interpret solubility graphs/curves
In Good Notes
Identify which separation technique works best in a given situation i.e. filtration, evaporation, distillation or chromatography.
See Good Notes
How do you set up the apparatus for filtration?
Put filter paper into a funnel
Place the funnel on top of a flask
Then pour the liquid with the insoluble solid in through the filter paper in the funnel
Let the water drip through
How do you set up the apparatus for evaporation?
Pour a solution into a boiler tube
Place it above a bunsen burner
Heat it up so the solvent evapourates
You will be left with the solute
How do you set up the apparatus for distillation?
Connect a flask full of a solution to a condenser which is connected to an empty flask at the other end
Connect a rubber tube to the bottom hole of the condenser and another one at the top
Place the full flask on top of a bunsen burner
Place a thermometer into the full flask
Turn on the bunsen burner and let the steam travel through the condenser then cool down fill the empty flask with water vapour
How do you set up the apparatus for chromatography?
Fill a beaker up with water
Get a strip of paper and draw a dot on it with the ink
Lay the strip of paper over a pencil which is ontop of the beaker so the paper is just touching the water
Compare evapouration and distillation?
Evapouration is turning a liquid to a gas under the influence of heat however distillation is obtaining a gas from a liquid through boiling and then condensing it back to liquid.
Thye both rely on heat to boil the liquid to create steam
How can chromatography be used in different scenarios?
You can use it to see what nutrients are in different foods
You can find exact paint colours for paint repair by looking at the pigment composition of paint
Dectectives can see what type of pen was used to write a note
