Reverse Osmosis

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Reverse Osmosis
2
Reverse Osmosis
semipermeable membrane
pressure
fresh water
salt water
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Reverse Osmosis
Pressure here
Water
Solution
Semipermeable membrane
Kelter, Carr, Scott, Chemistry A Wolrd of Choices
1999, page 267
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The pressure required to allow for no transport
of solvent across the membrane is called the
OSMOTIC pressure and obeys the relation
                                                  
                                                  
                  Osmotic pressure has a great
effect on living CELLS, because their walls are a
semipermeable membrane.
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Applied pressure needed to prevent volume increase
Osmotic pressure
Solution
Pure solvent
Net movement of solvent
Semipermeable membrane
Solute molecules Solvent molecules
The pressure required to allow for no transport
of solvent across the membrane is called the
OSMOTIC pressure and obeys the relation
                                                  
                                                  
                  Osmotic pressure has a great
effect on living CELLS, because their walls are a
semipermeable membrane.
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Net Solvent Flow
Net flow of solvent
Dilute solution
Net flow of solvent
Concentrated solution
Solute particle
Solvent particle
Ralph A. Burns, Fundamentals of Chemistry 1999,
page 430
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Dissociate in Water
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Dissolving of NaCl
Timberlake, Chemistry 7th Edition, page 287