Investigate how the Concentration of a Sucrose Solution affects the Rat

Investigate how the Concentration of a Sucrose Solution affects the Rate of Osmosis Introduction: Diffusion is the movement of particles from a high concentration to a low concentration until they are spread out evenly. An example of diffusion is when an aerosol is sprayed. The particles spread out from the high concentration at the nozzle into the rest of the room and that is how the smell moves. Osmosis is the passage of water molecules from a weaker solution to a stronger solution through a partially permeable membrane. Osmosis is a type of diffusion involving water - the water molecules move from a weak solution (with a high concentration of water) into a strong solution (with a low concentration of water). The cell membrane in a plant cell is partially permeable - it has small holes that can let in small molecules but not large ones. This allows water through and therefore allows osmosis. When the cell has all the water it can take inside of it the osmosis process stops. The water pushes up against the cell wall which is strong enough to stop it bursting. The cell is turgid and the plant needs turgid cells to give it rigidity and allow it to stand upright. If the cell has not enough water in it, it is flaccid and doesn't support the plant which goes limp. In order to prepare for my experiment I did a preliminary experiment to get an idea of how I would do my real experiment and what apparatus and solutions I would need. I weighed 11 potato chips and put them into separate boiling tubes. I filled each boiling tube with a different concentration of a sucrose solution from 0 molars (water) through to 1.0 molar with 0.1M intervals in between. After 30 minutes I removed the potato chips and measured their mass. I found that the chips in the concentrations of 0M to 0.2M had increased in mass and the rest had decreased in mass. For my experiment I have chosen to use five concentrations of sucrose solution - 0.0M, 0.1M, 0.2M, 0.3M and 0.4M. I have chosen these concentrations for two reasons. Firstly they cover the point at which the increase in mass changes to a decrease and therefore I can hopefully find the equilibrium where the mass stays the same, and secondly they are all at equal intervals so it will be easy and accurate to draw a graph for my results. Prediction: I predict that out of the five potato chips used in the experiment at least two will... ...tato chip in the solution for different time periods. I could then compare the gradients of the lines of best fit for the 5 different times, and also draw graphs for each molarity across the 5 time periods. I could also do an experiment using the same concentrations as I did in this experiment, but measuring the mass of the potato chips after every 3 or 4 hours until the mass stays the same, and see how long potato chips in different solutions took to reach a final mass and to see how large it's mass would get. Finally I would like to do the same experiment as I did here, but try it out on different types of plants and compare the rates of osmosis of the different plants. This would give an idea of which plants were more efficient at taking up water and I could see what types of plants had the fastest rate of osmosis, and whether there was a link between the rate of osmosis in a plant and the habitat it exists in. For example I might find that plants that live in hot, dry conditions have a faster rate of osmosis than plants which live in cold, wet environments. These experiments would help give a better idea of how the rate of osmosis is affected by the concentration of a solution.