Part A · Mixtures and recovery Separating and purifying substances mind map

Mixtures

• Composition: Pure: one element / compound; mixtures vary
• Purity evidence: Sharp melting point; compare reference and conditions
• Solution: Solute dissolves in solvent; solubility depends on conditions
• Choose method: Insoluble solid: filter; dissolved solid: crystallise
• Other methods: Miscible liquids: fractionate; dissolved dyes: chromatography
• Sand and salt: Dissolve salt → filter sand → crystallise filtrate

Solid recovery

• Filtration: Residue stays; filtrate passes; dissolved salt passes too
• Crystallisation: Concentrate gently → cool → filter crystals → wash / dry
• Heating safely: Avoid boiling dry; evaporation loses the solvent

Distillation

• Simple: Evaporate solvent → condense → collect distillate
• Apparatus: Measure vapour temperature; coolant enters lower inlet
• Safety: Never heat sealed apparatus; flammable solvents need care
• Fractional: Repeated vaporising / condensing enriches lower-boiling liquid
• Ink practical: Distillation recovers solvent; chromatography examines dyes

Connections

• Mixtures → Solid recovery: Solubility determines solid recovery.
• Mixtures → Distillation: Boiling-point differences enable distillation.