Essay on Osmosis
Every cell has a membrane which is selectively permeable, meaning that they only allow certain substances through. Osmosis is a particular kind of diffusion, involving the movement of water molecules through a semipermeable membrane. The diffusion takes place when the molecules of a substance move from a place of low concentration to a place of high concentration. The chosen independent variable for this experiment was the temperature of the water. Osmosis is defined as the movement of water molecules across a semipermeable membrane from a region of low solute concentration to an area of high solute concentration.
The aim of this experiment was to determine the change in osmosis when the temperature of water was increased by weighing each piece of rhubarb before and after it was left in the water. The hypothesis for this experiment was that the increase in the water temperature would increase the rate of osmosis resulting in a lighter or heavier rhubarb. The independent variable during this experiment was the change in the water temperature, the dependent variable was the change in mass of the rhubarb due to osmosis.
As shown in the table and graph above it is safe to say that the change in mass gained by the rhubarb due to osmosis through the water's temperature does infact increase as the temperature rises. As seen in table 1, when the water's temperature was only 20 degrees warm, the osmosis process occurred slower, making the rhubarb gain on average a mass of ___ grams. Comparing this to that of the results of the gain of mass in the 60 degree water on an average of a ___ grams. It can be obtained because of the rise in the temperature of the water, and the increase in water particles movement due to this that it does influence the rate of osmosis which occurred. Furthermore, since the rhubarb cubes are smaller, there is less distance needed for small cells to interact, allowing information to be transmitted from the nucleus to the rest of the cell more easily. Smaller cubes would have proportionally more surface area per unit volume for material exchange with their surroundings. As a result, the smaller the rhubarb cubes are, the higher the rate of osmosis, resulting in a greater percent shift of mass.
Random errors that could have occurred during this experiment come from not measuring out the water amount and temperature to the exact amounts for every individual test. If per say, the water temperature was at 58 degrees for test one, 62 degrees for test 2 and 60 degrees for test 3, the minor change in the temperature may in fact lead to inaccurate results. Cutting the rhubarb into the exact same shape and weight can also lead to a random error, it is unlikely that every piece of rhubarb would end up the exact same, and because of this there could be certain variables which are not performed correctly. Leading to inaccurate results. If the piece of rhubarb were left in the water for more or less time then it was supposed to be in there for, it could also affect the osmosis rates.
Systematic errors that could have occurred during this experiment could have come from the scale not being set up correctly, or being broken and unable to get the correct weights for each test during this experiment. If the thermometer was broken, it could have meant an inaccurate temperature of water for each test, leading to different rates of osmosis occurring and through this, gathering incorrect data for each test.
The hypothesis for this experiment was that the increase in the water temperature would increase the rate of osmosis within the rhubarb. The results that were gathered during this experiment help to support the hypothesis. With an average gain of mass of ___ grams in 20 degree water, ___ grams in 40 degree water and ___ grams in 60 degree water, it is safe to agree that the rate of osmosis got faster as the temperature increased, leading to the increased gain of mass in the rhubarb.
