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11 Cards in this Set
- Front
- Back
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What is extraction?
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Transferring a solute from one solvent into another
(Liquid-liquid extraction) |
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Why use ether? for the solvent?
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Because it is a water-immiscible solvent (nonpolar)
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Why do two layers form?
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They do not mix (one is polar, the other is nonpolar)
Also, two solvents have different density Less dense solvent will become top layer |
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How does extraction work?
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Two solvents are immiscible and due to differences in physical properties, molecule A is more soluble in solvent A (or B in B)
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Ether layer?
Organic layer? Aquesous layer? |
Ether layer = organic layer - NONPOLAR layer (water-immiscible)
Aqueous layer - POLAR layer (water-miscible) |
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How do you determine which one is the organic layer?
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Add a drop/two of water into each layer
If the water dissolves right away - aqueous layer If the water forms droplets - ORGANIC/ETHER layer |
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What is emulsion? and how do you get rid of it?
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Emulsion is when usually-immiscible solvents get mixed.
You can top the vial or stir the mixture gently You can get rid of it by adding brine (salt in water) It would make aqueous layer even more polar then they are going to be separated |
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What’s better: One large volume extraction, or lots of small volume extractions?
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Lots of small volume extraction
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Drying agent
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After an organic solven has been shaken with aq solution, it will be wet. Insoluble drying agent (Na2SO4) will hydrate the water and make it dry.
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Extraction scheme
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IDK you tell me
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How to properly remove layers
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Always remove bottom layer!!
Hold vials next to each other while transferring liquids |
