separation techniques
Flashcard Set: Separation Techniques and Water Sustainability
Flashcard 1
Q: What is the principle of magnetic attraction?
A: Magnetic attraction separates magnetic materials from non-magnetic ones. Example: Removing iron filings from a mixture of sand and iron.
Flashcard 2
Q: What is the principle and application of filtration?
A: Filtration separates insoluble solids from liquids using filter paper and a funnel. Example: Filtering coffee grounds from brewed coffee.
Residue: Particles left on the filter paper.
Filtrate: Liquid that passes through the filter.
Flashcard 3
Q: Describe the process of evaporation to dryness and its limitations.
A: Evaporation to dryness removes the solvent by heating, leaving behind the soluble solid. Example: Obtaining salt from seawater.
Limitations: Not suitable for solutes that decompose or are damaged by heat.
Flashcard 4
Q: What is crystallisation and when is it used?
A: Crystallisation separates soluble solids from a solution by evaporating part of the solvent to form crystals. Example: Producing sugar crystals from a sugar solution.
Note: Used for substances that decompose when heated to dryness.
Flashcard 5
Q: Explain simple distillation and the precautions necessary for its operation.
A: Simple distillation separates a single liquid from a solution by boiling off the solvent and condensing the vapour. Example: Purifying water from saltwater.
Precautions:
Add boiling chips to prevent bumping.
Place the thermometer at the condenser’s inlet.
Ensure water circulates correctly in the condenser.
Flashcard 6
Q: How does fractional distillation differ from simple distillation?
A: Fractional distillation separates two or more miscible liquids with different boiling points using a fractionating column. Example: Separating ethanol from water.
Flashcard 7
Q: What is the principle of using a separating funnel and an example of its use?
A: A separating funnel separates immiscible liquids based on their densities. Example: Separating oil from water.
Flashcard 8
Q: Describe the process and precautions for paper chromatography.
A: Paper chromatography separates solutes based on their solubility in a solvent. Example: Identifying pigments in an ink sample.
Precautions:
Use non-soluble materials like pen lead instead of ink.
Keep spots above the solvent level.
Allow the solvent front to approach the top of the paper.
Flashcard 9
Q: What methods are suitable for separating solid-solid mixtures?
A:
Magnetic Attraction (if one component is magnetic).
Sieving (for different particle sizes).
Hand Sorting (for large, distinguishable particles).
Flashcard 10
Q: What methods can be used for separating solid-liquid mixtures?
A:
Filtration (for separating solids from liquids).
Evaporation (to obtain the solid by removing the liquid).
Crystallisation (to purify the solid if it is dissolved).
Flashcard 11
Q: How are liquid-liquid mixtures separated based on their miscibility?
A:
Miscible Liquids: Use Fractional Distillation to separate based on boiling points.
Immiscible Liquids: Use a Separating Funnel to separate based on density.
Flashcard 12
Q: What are some common applications of separation techniques in everyday life and industries?
A:
Water Treatment: Distillation and Reverse Osmosis for purifying water.
Food Safety: Filtration and Crystallisation in food production.
Waste Management: Evaporation and Fractional Distillation for recycling waste.
Flashcard 13
Q: Why is water considered a precious resource?
A:
Population Growth: Increases demand for water.
Climate Change: Alters water availability.
Pollution: Contaminates water sources, making them unsafe.
Flashcard 14
Q: How does Singapore ensure a sustainable water supply?
A:
NEWater: Advanced filtration and reverse osmosis to recycle used water.
Desalination: Converts seawater into potable water.
Rainwater Harvesting: Collects and stores rainwater.
Water Conservation Initiatives: Promotes efficient water use and recycling.