Separation Techniques

Question 1

What are separation techniques used for?

Answer 1

to separate mixtures

Question 2

What is a mixture?

Answer 2

a combination of two or more elements/compounds which are not chemically joined together

Question 3

What is a compound?

Answer 3

two or more elements chemically joined together

Question 4

name five separation techniques

Answer 4

• filtration
• distillation
• evaporation
• crystallisation
• paper chromatography

Question 5

How does filtration work?

Answer 5

separates an undissolved solid from a mixture of the solid and liquid/solution
(e.g. sand and water)

Question 6

What are the two types of distillation?

Answer 6

• simple

- fractional

Question 7

How does simple distillation work?

Answer 7

separates a liquid from a solution

e.g. water from salt solution

Question 8

How does fractional distillation work?

Answer 8

separates two or more liquids that are miscible (mix together) with one another

Question 9

How does evaporation work?

Answer 9

separates a dissolved solid from a solution (solid soluble in hot/cold solvent)
(e.g. sodium chloride from salt solution)

Question 10

How does crystallisation work?

Answer 10

separates a dissolved solid from a solution (solid more soluble in hot solvent)
(e.g. copper sulfate in copper sulfate solution)

Question 11

How does paper chromatography work?

Answer 11

separates substances that have different solubilities in same solvent
(e.g. coloured ink mixed in black ink)

Question 12

Methods of separating compounds

Answer 12

• thermal decomposition

- electrolysis