MIXTURES AND SEPARATIONS

 Al D. Deacon 

Founder: Gold'N Geniuz 

Physicist and Educator 

1. Distinguish Between Pure Substances and Mixtures

• Pure Substances: Composed of only one type of particle (element or compound).
  • Examples: Oxygen (O₂), Water (H₂O), Sodium Chloride (NaCl).
• Mixtures: Contains two or more substances physically combined.
  • Examples: air (gas mixture), saltwater, sand, and iron filings.
• Key Differences:
  • Pure substances have fixed composition and properties.
  • Mixtures can be separated into their components physically.

2. Distinguish Among Solutions, Suspensions, and Colloids

Property	Solution	Colloid	Suspension
Particle Size	Small (<1 nm)	Medium (1–1000 nm)	Large (>1000 nm)
Appearance	Transparent	Cloudy but uniform	Cloudy and settles over time
Settling of Particles	Does not settle	Does not settle	Particles settle
Example	Saltwater	Milk, Fog	Muddy water, Flour in water

3. Identify Different Types of Solutions

• Solid in Liquid—Salt in Water
• Liquid in Liquid—Vinegar (Acetic acid in water)
• Gas in Liquid—Carbonated drinks (CO₂ in water)
• Gas in Gas—Air (O₂, N₂, CO₂ mixture)
• Solid in Solid—Alloys (Brass = Copper + Zinc)

4. Investigate the Effect of Temperature on Solubility of Solids in Water

• Hypothesis: Increasing temperature increases solubility.
• Experiment:
  1. Dissolve a fixed amount of salt/sugar in cold water and record solubility.
  2. Repeat with warm and hot water.
  3. Observe solubility changes.
• Conclusion: Higher temperature allows more solute to dissolve (except for some like calcium sulfate).

5. Apply Suitable Separation Techniques Based on Properties

Mixture	Property Used	Separation Method
Sand and Water	Particle Size	Filtration
Salt and Water	Boiling Point	Evaporation/Distillation
Alcohol and Water	Boiling Point	Fractional Distillation
Iron and Sand	Magnetism	Magnetic Separation
Oil and Water	Density & Immiscibility	Decanting/Separating Funnel

6. Describe the Extraction of Sucrose from Sugar Cane

1. Harvesting and Crushing: Sugar cane is cut and crushed to extract juice.
2. Clarification: Lime (CaO) is added to remove impurities.
3. Evaporation: The juice is heated to remove excess water.
4. Crystallization: The concentrated syrup is cooled to form sugar crystals.
5. Centrifugation: Separates sugar crystals from molasses.
6. Drying and Packaging: The sucrose crystals are dried and packed.