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Osmosis (Adapted from a lecture by Eve Oram; www.mrothery.co.uk/studentswork/student%20presentations/osmosis%20presentation.ppt ). Osmosis is the NET movement of water molecules across a partially-permeable (selectively-permeable) membrane.
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Osmosis(Adapted from a lecture by Eve Oram;www.mrothery.co.uk/studentswork/student%20presentations/osmosis%20presentation.ppt) Osmosis is the NET movement of water molecules across a partially-permeable (selectively-permeable) membrane. Water molecules move randomly with a certain amount of kinetic energy….
Distilled water separated by apartially-permeable membrane Water molecules are randomly moving from one side of the membrane to the other, but there is NO NET OSMOSIS.
Osmotic Potential – the potential that water molecules have to moveDistilled (or pure) water has the highest potential (zero).When water has another substance dissolved in it, water molecules have less potential to move because they are attracted to the substance. Thus, the osmotic potential becomes negative.
If a substance is dissolved in the water, the kinetic energy of the water is lowered. This is because some water molecules will aggregate on the surfaces of the molecules of the dissolved substance.
Water molecules movefrom higher to lowerwater potential Net movement stops when the system is again in equilibrium. Random motion continues as before.