Filtration and crystallisation

Question 1

What is filtration?

Answer 1

• Method of separating mixtures

- Separates insoluble solids from liquids

Question 2

What are the two ways of separating soluble solids from solutions?

Answer 2

• Evaporation

- Crystallisation

Question 3

Process of evaporation:

Answer 3

• Solution in evaporating dish
• Heat slowly
• Solvent evaporates
• Solution become concentrated
• Crystals form
• Heat until only dry crystals are left

Question 4

When can evaporation be used?

Answer 4

• Only if salts don’t decompose when heated.

Question 5

Process of crystallisation:

Answer 5

• Solution in evaporating dish
• Heat slowly
• Solvent evaporates
• Solution become concentrated
• Crystals forming
• Remove from heat and let solution cool
• Crystals form and become invaluable
• Filter crystals
• Leave in warm place to dry

Question 6

How can filtration and crystallisation be used to separate rock salt?

Answer 6

• Grind
• Dissolve
• Filtering
• Evaporation/Crystallisation