1. SEPARATION TECHNIQUES
Filtration and Evaporation
Distillation
Paper Chromatography

2. Filtration and Evaporation
Filtration is a method for the separation of the parts of a heterogeneous mixture.
When students mixed two common substances, a heterogeneous mixture was formed.
There was a precipitate in a solution.

3. Filtration and Evaporation
In preparation for the filtration, the filter paper must be folded into a cone.
The students may be measuring the mass of the filter paper so that they can determine the mass of the precipitate after the experiment.

4. Filtration and Evaporation
The cloudy, heterogeneous mixture is carefully poured into a funnel that has been set up with filter paper.
Notice that the filtrate is being collected in a beaker.

5. Filtration and Evaporation
The precipitate in the original filtrate beaker must be washed out using the stirring rod and the wash bottle.

6. Filtration and Evaporation
Evaporation is a method for separating the components of a homogeneous mixture.
After filtration, the students evaporated the filtrate solution to separate it from any dissolved solute.

7. Filtration and Evaporation
The liquid (solvent) from the filtrate solution will evaporate leaving behind any dissolved solute.

8. Filtration and Evaporation
Meanwhile, the insoluble solid that was collected on the filter paper was dried in an oven.
By taking the mass of the filter paper before the filtration and the mass of the paper and solid after it dries…
…the mass of precipitate can be calculated

9. Distillation
Distillation is a method for the separation of the components of a homogeneous mixture.
The basis for separation is the different boiling points of the components in the liquid.

10. Distillation
The distillation apparatus will be used to separate some of the components of imitation vanilla.

11. Distillation
The component with the lowest boiling point will boil off first.
The vapor is condensed and this distillate is collected in the receiving flask.

12. Distillation When all of a particular component is gone…
…the temperature will rise to the next boiling point
and that substance will form the next distillate.

13. Imitation Vanilla Flavor
Ingredient
Chemical formula
Boiling point
(1 atm)
Water
H20
100C
propylene glycol
C3H8O2
188C
vanillin
C8H8O3
285C
caramel color
mixture of complex sugars
N/A
0.1% sodium benzoate
NaC6H5CO2
phosphoric acid
H3PO4
158C
ethyl vanillin
C9H10O3

14. Paper Chromatography
Paper chromatography is an easy way to separate the soluble components of a homogeneous mixture
We will perform a chromatographic sparations of the pigments in felt pens

15. Paper Chromatography Specific vocabulary words include:
Mobile phase
Solvent
Stationary phase
Paper
Separation is based on:
Solubility of the sample in the mobile phase
Molecule size
(and other factors)