Investigation into the Rate of Osmosis in Potatoes and to find out the Sucrose Concentration of the Potato.
In order to carry out this investigation, I first have to define the terms of the objectives so that an understanding is present and a clear process to acquire the answer can be devised.
What is Osmosis?
Osmosis is the process by which water molecules pass through a partially permeable membrane from an area of high concentration of water to an area of lower concentration of water (e.g. from distilled water to concentrated sucrose solution). The reason for this is because of the natural tendency of water to spread from regions of high concentration to regions of low. This spreading process is called diffusion.
Several examples of osmosis can be seen in nature that can give a better idea of what is happening during osmosis. E.g. if water is withheld from a flowering plant then the plant will wilt.
If bacterial cells are placed in concentrated salt-water solution, they collapse and die. Human blood cells placed in fresh water expand and burst.
The reason for these events is because of the partially permeable membrane present in osmosis. Water molecules are very small (one oxygen atom and two hydrogen atoms) while sugar molecules are many times larger. The membrane has very small holes or pores in it that allows water molecules to pass through them because they are small enough, but do not allow sugar molecules to pass through because they are too big. Therefore, when the water molecules are diffusing through the membrane, the side of the membrane that is gaining water will expand and increase in mass and volume, as the other side decreases in mass and volume by losing the water molecules. Thus, osmosis is the movement of...