Discussion
The effect of different concentration on the percentage change in mass while osmosis was observed, and each experiment was performed by calculating the initial and final masses of the potato pieces and the small bag of Visking tube.
According to the table 1 and graph 1, the effect of concentration was identified as the concentration of sucrose increase the percentage change in mass of potato also increase because sucrose is hypertonic solution which means that it has a higher amount of particles dissolved in the solution, while a hypotonic solution such as water where there are fewer particles dissolved. When the potato was put in sucrose concentration where the water potential is larger than that of the potato to the sucrose then mass increased. As it can be seen from the graph, the highest percentage change in mass was in the pure water, the percentage was constituted
…show more content…
Firstly, the width of the potatoes might not be all the same as they were cut imprecisely, so there might be a random error because not following standard width, which should be constituted at 1-2 mm thick. Secondly, not enough experiments with different independent variables. Experiment under the same independent variable was only conducted one times. Thirdly, the electronic mass kept on changing from 2.0-2.6 g. Human errors in observing the osmosis, pH of the potato slices such as touching potatoes and a small number of trials, which may have led to unreliable results. One of the important weaknesses of the experiment was unstable time periods with watch glass such as not removing the potato slices or Visking tube at the same time. Moreover, the results are not valid enough in appropriate level of investigation and observation. The confidence of received results is reliable at some extent. An effort is made to make the experiment as precise as possible. The level
Introduction The purpose of this Lab was to identify the density of the unidentified object and determine what substance the unidentified object given by the teacher was. The density calculated in the experiment will stay the same because the density of the unidentified object will stay constant. The Independent Variable of this experiment was the calculated density and the unidentified object given. The Dependant Variable for this experiment was the density.
a. Water boils to produce steam at 100 C (212 F) b. Water produces gas with sodium metal c. Water and oil separate when combined d. Water dissolves sugar 22. In the experiment, students put brine shrimp in water with different concentration of salt and counted the number. Which of the following changes to the experiment will increase confidence in the validity of the result? a. Count the number of dead brine shrimp instead of living brine shrimp b. Add more brine shrimp to the water with the highest salt concentration c.
Due to water’s polar structure, ions in some compounds attract and form bonds with water molecules, forming hydrates. A hydrate is a salt that has water molecules trapped within its crystals. Every hydrate has a certain number of water molecules weakly bonded to the salt as follows: salt • number of water molecules Anhydrous salts are salts that can form hydrates but which have had all the water driven off, usually by heat. By heating the Copper (II) sulphate hydrate until its color changes from blue to white, the compound can be decomposed into CuSO4, a white crystal, and H2O gas, represented as follows: CuSO4 • xH2O(s)
The isotonic point is the point in which osmosis causes the concentrations of either side of the cell wall to reach an equilibrium (balance). The original experiment involved placing gummy bears in water and sugar and salt solutions (Gummy bear osmosis, 2022). The experiment was modified to further investigate the effect of varying NaCl concentrations on the mass of potatoes.
Additionally, it was difficult obtaining a piece of rhubarb that was thin and particularly red, therefore the effect could not be best observed in the cells. Part B: Design your own experiment Parts of this practical were taken and slightly altered from the following link http://www.markedbyteachers.com/gcse/science/investigate-the-effect-of-surface-area-on-osmosis-in-potato-tissue.html Aim: To observe the effect different surface area: volume ratios have on osmosis in potato tissue. Hypothesis: If the potato has a larger surface area: volume ratio, the quicker osmosis will take place and the larger the mass will be at the end of the experiment, therefore the difference in mass of the potatoes from the start of the experiment to the end of the experiment will be larger. Additionally, the potato pieces left in a saltwater solution will decrease in mass, whereas the pieces left in water will increase in mass.
For this lab I will be using water and sucrose to demonstrate the rate of osmosis. In this lab I will be exploring how temperature impacts the rate of osmosis by placing pieces of potato of equal size in solutions of different temperatures and observing the change in mass of potato after a given period of time. The change in mass will indicate the rate of osmosis.
Finally we compared these two methods in order to decide which method is more suitable. References http://www.middleschoolchemistry.com/lessonplans/chapter3/lesson1 http://chemistry.about.com/od/waterchemistry/f/What-Is-The-Density-Of-Water.htm
The final mass could be far off due to the water and chunks of expanded gummy bears found in the beaker, leading to an inaccurate result. As well, for the sugar solution, the result could have been different if a more accurate measurement of the sugar needed was made. For the specific result, the hypothesis stated, the sugar solution needed to have an equal amount of sugar content to the gummy bear which did not occur. Ensuring that the beaker contained 10 grams of sugar was off, due to prerequisite calculations that lead to too much liquid in the beaker that needed to be removed. To be correct, the hypotheses that were wrong could
This also shows how much water was transferred from the egg to the sugar solution. The higher the percentage of corn syrup was, the faster the rate of osmosis was. As a result, the egg placed in 75% corn syrup, 25% filtered water had the lightest weight (0.5 oz), while the egg placed in 25% corn syrup, 75% filtered water weighed 2 oz. Overall, the importance of this lab was to understand the process of osmosis and how it differs depending on the type of
Each group was assigned a different percent of sucrose solution out of the four variables; 0% , 5%, 10%, and 15%. After we filled the beaker we then got two potato cores. Once we had the cores we cut the skin off the ends. Following this we then cut the two potato cores into four 2.00 cm potato cores. After they were cut into 2.00 cm each we found the mass.
By using the same mass of potato slices and putting them in different concentration of solutions for a specific amount of time will tell us how the concentration changes the mass of the potato slice. Therefore changing the rate of osmosis. Hypothesis: I predict that, if the piece of potato was put into a solution that has a high concretion of sucrose then the potato slice would lose mass as it would lose water from its cells because the water is moving out of the cell from a high concentration to a low concentration of water through a semi- permeable membrane. The cell is hypotonic and the solution is hypertonic.
The hypothesis we came up with for this project was that in the distilled water there wouldn't be no change in the potato, we wouldn’t see a gain or loss with the water sitting in the beaker. The beaker with the 30% Sucrose and Distilled water we predicted that there was going to be weight gain to the potato. And for the distilled water with the 30% sucrose and we predicted weight loss. But the results came out to be the first bag content being isotonic the second bag came out to be hypotonic and lastly the result came out to be
This experiment has to be carried out carefully
Biology Design Practical Joshua Edwards What are effects of the volume of a potato and the amount of weight it loses when placed in salt solution? Introduction This design practical uses a potato’s surface area to volume ratio to see what affects it has on osmosis in different concentrations. Osmosis is the movement of water molecules through a cell membrane into an area of a higher solute concentration. The movement goes the way of the solvent with more solute because the lower solute concentration is drifting through balancing the ratio of solute per solvent (En.wikipedia.org, 2018).
This experiment is to investigate the relationship between solute concentration and the movement of water through semipermeable membrane by the process of osmosis. The purpose of this The Visking tubing apparatus establishes the osmosis procedure. The Visking tubing is a semipermeable membrane filled up with concentrated sucrose solution. The surface of the semipermeable membrane symbolizes the visking tubes and the mixture demonstrates the cytoplasm. If the Visking tube is absorbed in water, after a period of time, it will be have water inside water, this is because the water molecules can pass through the tubing, while the larger sugar molecules cannot diffuse out from the tubing because the size of sugar molecules do not allow it to go through the tubing.