1. Particle size
1.1. Separation techniques based on particle size involve sorting components with different physical sizes.
1.1.1. sublimation
1.1.1.1. - It separates volatile solids that convert directly to vapor upon heating from non-volatile solids. - e.g Heating a mixture of iodine and sand causes iodine to sublime into vapor, leaving the sand behind. The vapor can then be cooled and condensed to recover the iodine.
1.1.2. mechanical picking
1.1.2.1. - It separates components based on physical characteristics such as shape, size, or appearance. It involves manually or mechanically selecting and removing substances that differ visibly. - e.g Removing stones or husk particles from grains.
1.1.3. filtration
1.1.3.1. - It separates components based on physical characteristics such as shape, size, or appearance. It involves manually or mechanically selecting and removing substances that differ visibly. - e.g Removing stones or husk particles from grains.
2. Density
2.1. Techniques that separate substances by mass per unit volume, with denser materials settling or being pushed down by gravity or centrifugal force.
2.1.1. gravity separation
2.1.1.1. -It separates components with different densities in a mixture. - e.g When a mixture of sand and chalk powder is added to water, the denser sand particles settle at the bottom, while the lighter chalk floats on the surface, allowing for separation.
3. Magnetism
3.1. Magnetism separates magnetic materials from non-magnetic ones in a mixture.
3.1.1. magnetic separation
3.1.1.1. - It utilizes a magnet to attract ferromagnetic materials like iron, cobalt, or nickel, leaving non-magnetic substances behind. A magnet or magnetic belt is used to separate the magnetic component from the mixture. - e.g Separating iron filings from sulfur using a magnet.
4. Boiling point
4.1. This technique separates substances based on their boiling points, allowing one component to evaporate first upon heating the mixture.
4.1.1. simple distillation
4.1.1.1. -It separates a liquid mixture into its components based on different boiling points through evaporation and condensation. -Example: When a saltwater solution is heated, water evaporates first, leaving salt behind as the residue
4.1.2. fractional evaporation
4.1.2.1. -It separates liquefied gases by gradually evaporating them at their respective boiling points. -e.g When liquefied air is evaporated, nitrogen, with the lowest boiling point, boils off first, leaving oxygen behind. Continued evaporation eventually separates all the components.
4.1.3. fractional distillation
4.1.3.1. -It separates miscible liquids with close boiling points. The mixture is heated, and the liquid with the lower boiling point evaporates first, leaving the higher boiling point liquid behind. The vapor is then condensed to recover the separated liquid. - e.g Separating components like gasoline and diesel from petroleum.
4.1.4. preferential liquefaction
4.1.4.1. - It separates gases based on their ability to liquefy under pressure. When a mixture of gases is subjected to high pressure, the more easily liquefiable gas condenses first, leaving the less liquefiable gas behind. - e.g Separating ammonia from hydrogen, where ammonia liquefies under pressure, while hydrogen remains gaseous.
5. Melting point
5.1. Techniques separate mixtures by identifying the temperature at which components transition from solid to liquid. It's used when one substance melts at a lower temperature than the others.
5.1.1. -It separates substances that transition directly from solid to gas without passing through the liquid phase. -e.g. Dry ice (solid CO₂) sublimates directly into gas at room temperature.
6. Solubility
6.1. These methods use differences in solubility to separate components of a mixture.
6.1.1. fractional crystallization
6.1.1.1. - It separates components based on their differing solubilities in the same solvent. - e.g In a mixture of KNO₃ and NaCl, both dissolve in water, but NaCl, being less soluble, crystallizes first as the solution cools. The NaCl crystals are filtered out, and KNO₃ crystallizes from the filtrate upon further cooling.
6.1.2. solvent extraction
6.1.2.1. - Solvent extraction separates components by dissolving one in a solvent while others remain undissolved. -e.g. Separation of sulphur and iron. Sulphur dissolves in carbon disulphide, leaving iron solid. After filtering out the iron, carbon disulphide evaporates, leaving sulphur behind.
7. State
7.1. The techniques separate components that exist in different physical states, such as liquid, solid, or gas, without changing their phase.
7.1.1. separtion funnel
7.1.1.1. It separates two immiscible liquids by allowing them to settle into different layers, where the denser liquid can be drained from the bottom. Example: In an oil-water mixture, oil (less dense) floats on top of water (more dense), allowing for easy separation by draining the water from the bottom
7.1.2. distillation
7.1.2.1. -It separates a solvent from a solution by boiling off the solvent, which is then condensed back into liquid form. -e.g. Separating water from saltwater, where water evaporates and is collected, leaving the salt behind.