Diffusion refers to a process which molecules intermingle because of their kinetic energy that goes in all directions. They tend to move from places with higher concentration of the molecule to lower concentrated area. It is defined by Pearson as the net movement of molecules down their concentration gradient.
e.g. perfume spreading across room
Osmosis
Osmosis is a special case of diffusion that only happens in water. Where there is a semi- permeable membrane once again from higher concentration to lower concentration. The picture below illustrates
an example:
For this class, we reviewed basic concepts of diffusion and osmosis, and went through key words such as water potential, molecular motion, hypertonic, hypotonic, isotonic etc. After, we started on 2 labs relating to osmosis. For our first lab, we put different solutes of various molarities into semi- permeable membrane and we massed and put them in a beaker with water outside of the membrane. After 30 minutes, we massed them again and determined the mass change thus allowing us to know the molarity of each of the solutes.
Link of results: https://docs.google.com/spreadsheet/ccc?key=0AvnnOJLj_iJAdFZQSlo0QjdONVBRQ2ZMcExvSVdkZEE#gid=0
After, we started our second lab and we soaked the potatoes inside the solutes this time and the results will be determined and posted soon.
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