Separation techniques

Question 1

Pure Substances:

Answer 1

• Compounds, elements
• Single substance made out of one type of particle.

Question 2

Mixtures:

Answer 2

• Two or more substances are mixed together.
• Do not react or behave same way as pure substances.

Question 3

Separating by particle size:

Answer 3

• Sieving - used to separate solids with different particle sizes.
• Gravitational filtration - when you rely on the weight of the solid particles to filter the two materials.
• Vacuum filtration - Useful if particles are light.

Question 4

Filtration:

Answer 4

Used to separate an insoluble substance from a soluble substance.
- Separate heterogenous mixtures.
- Porous barrier to separate the solid from the liquid.

Question 5

Separation by density:

Answer 5

-Sedimentation : Dense materials drop to the bottom, decantation is when you pour the liquid at the top away.
- Separation funnels: Used when two substances dont mix, the tap at the bottom is used to clear out the more dense substance.
- Centrifugation: Is when a mixture is spun in a centrifuge to settle the particles may not settle naturally.

Question 6

Separation by boiling point:

Answer 6

• Evaporation: boil of the liquid (solvent) and it leaves with the dissolved material (solute).
• Distillation: uses evaporation to collect gases, then condensed and collected again as liquid separately.
• Fractional distillation: Used for mixtures with several different substances with different boiling points.

Question 7

Crystallization

Answer 7

• Separation technique that results in formation of pure solid particles from a solution containing the dissolved substance.
• As the solvent evaporates, the dissolved substance comes out of the solution and collects as crystals.
• Highly pure solids

Question 8

Separation by electric charge:

Answer 8

• Electrostatic separation can be used to separate charged solid particles from a gas.
• Chromatography: relies on stickiness of a material to a static medium, separates components of a mixture out.

Question 9

Magnetic separation:

Answer 9

• Used to separate a magnetic substance from a non-magnetic substance.