The hypothesis states that if the solution is hypotonic the results will decrease, if the solution is hypertonic the results will increase and if the solution is isotonic the solution will vary and or remain constant. In order to test the predictions of the hypotonic, hypertonic, and isotonic hypothesis for the solution made during the study, four samples of sucrose were taken and placed into two different beakers each containing a different concentration. Then dialysis tubing A was placed into beaker 1 with B, C, and D placed into beaker 2 for 45 minutes and weighted at 15 minute intervals. My finding in the study was that each of the four samples changed from their initial weight and for the most part accurately proved the hypothesis. …show more content…
The difference is that along with large molecules, living cells prevent molecules with positive charges and solubility. This is not representing in dialysis tubing, and is only found in living cells because the tubing is only based on molecular size (98). When referring the rate of diffusion, the concentration gradient influences the diffusion rate, based on the factors of temperature. The ability for molecules diffuse from high to low concentrations primarily depends on the concentration gradient between the two areas.(96-99). My hypothesis for the study is that in the hypotonic, hypertonic, and isotonic solutions, the direction and rate of osmosis will determine based on the concentration inside the dialysis tubing. My prediction is that if the solution is hypotonic the results will decrease, if the solution is hypertonic the results will increase and if the solution is isotonic the solution will vary and or remain constant.
Materials and Methods
In order to test the predictions of the hypotonic, hypertonic, and isotonic hypothesis for the solution made during the study, four samples of sucrose were taken and placed into two different beakers each containing a different concentration. Beaker 1 is 250- mL and contained 150-mL of 10% sucrose with dialysis tubing A, while beaker 2 (a large bowl) contained 1% sucrose, with dialysis tubing B, C, and D. Tubing A contained 10-mL with 1% sucrose. Tubing B
If we placed our chicken egg into a higher percentage of sucrose solution for a set period of 60 minutes then the egg will gain weight. If the egg gained weight then the sucrose solution it was placed in had a low concentration that would make it hypotonic. If the egg loses weight then sucrose solution it was placed in had a high concentration that made it hypertonic. If there is no change in weight in the chicken egg when placed in the concentration the solution will happen to be isotonic.
In this lab experiment, half our group observed and measured osmosis using dialysis tubes that were represented as the semipermeable membrane. It is permeable to water and other small molecules but is impermeable to larger molecules such as the sucrose solution used in each of the four beakers and tubing. The other half of our group observed the tonicity of sheep blood to determine whether the blood was isotonic, hypotonic, or hypertonic. The 85 g/dL of NaCl solution was the ideal isotonic number in relation to the sheep blood cells as well as a reference to the other observations of the solutions.
Hypothesis: If we add higher concentrations of sugar to the dialysis tubing, then the net movement of coffee into the dialysis tubing will increase.
The independent variable was the concentration of sucrose in the dialysis tubing we used as a simulated membrane.
The dialysis tubing will be clamped at one end in order to fill it and then clamped at the other end to seal the filled bag. If the bag is not soft and floppy, the experiment will not work. Blot a bag with a paper towel to absorb the moisture and weigh it, if this blotting process is not done it could interfere with the weight readings creating inaccurate information. After the bags of the solutions are prepared, they will be placed into five different beakers with different solutions. Beakers 1-4 will be filled with tap water and the fifth beaker is filled with 40% sucrose and water. Fill each beaker with just enough water or solution so that the bag is covered and place the bags in the beakers simultaneously and record each time. Every 10 min the bags are to be taken out, blotted, and weighed again before returning them back into their respective beaker for another 10 min. The process is repeated until you have reached 90 min. The weights should be recorded in grams (g).
In this experiment, we will investigate the effect of solute concentration on osmosis. A semi‐permeable membrane (dialysis tubing) and sucrose will create an osmotic environment similar to that of a cell. Using different concentrations of sucrose (which is unable to cross the membrane) will allow us to examine the net movement of water across the membrane.
Though the theory following the hypothesis is correct and the experiment was carried out with as much attention as possible in a high school laboratory, the results obtained were still indicative of a few errors and did not support the predicted hypothesis. From the results obtained it can be concluded that as the concentration of sucrose increases the average percentage change in mass decreases. This is because the salt concentration inside the potato cubes of 10%, 15% and 20% concentration is less that in the salt concentration on the sucrose solution, thus the three cubes submerged in the 10% - 20% concentrated solution lost mass (hypertonic). However the cube submerged
In this study we constructed we researched whether different sucrose concentrations affect the rate of osmosis. In order to do this, we constructed artificial cells out of dialysis tubing filled with 20% sucrose and 40% sucrose and weighed them every 10 minutes for 90 minutes. In doing so, we concluded that the higher the sucrose concentration, the faster the rate of osmosis.
The reasoning behind this experiment is the examine whether the rate of osmosis is changed due to a change in temperature. It was hypothesized that the rate of osmosis will increase as the temperature of the sucrose is increased. The rate of osmosis was tested by using the different jars full of different temperate water and testing how high the water rose on an osmometer over a span of 20 minutes. An osmometer is a tool used to measure rates of osmosis. The different temperatures tested on a sucrose solution were 5 degrees Celsius, 20 degrees Celsius, and 37 degrees Celsius. Rates of osmosis were higher in the hot water than in the cold water and control. The results showed that the rate of osmosis increased as the temperature increased, henceforth the hypothesis was supported. In conclusion, the experiment showed how changes in temperature affect the rate of osmosis.
There were several steps completed to prepare for the experiment. Three dialysis tubes were filled with approximately the same volume of distilled water and then were tied shut. The initial mass (in grams) of the tubes was taken using a triple beam scale. I then filled three 500 mL beakers with 400 mL of water each and dissolved different masses of solute (table sugar) in each beaker in order to make 5%, 10%, and 20% solutions. The beakers were labeled accordingly, and then 20 g, 40 g, and 80 g (respectively) of table sugar was weighed out using a digital scale and placed into the corresponding beakers. The sugar was stirred in using a stirring rod until all of the solute was completely dissolved.
Osmosis is defined as the tendency of water to flow through a semipermeable membrane to the side with a lower solute concentration. Water potential can be explained by solutes in a solution. The more positive a number is more likely it will lose water. Therefore should water potential be negative the cell the less likely it will lose water. In using potatoes the effects of the molarity of sucrose on the turgidity of plant cells. According to Clemson University, the average molarity of a White potato is between .24 M and .31 M when submerged in a sorbitol solution. This experiment was conducted with the purpose of explaining the relationship found between the mass in plants when put into varying concentrations of sucrose solutions. Should the potatoes be placed in a solution that contains 0.2M or .4M of sucrose solution it will be hypotonic and gain mass or if placed in .6M< it will be hypertonic and lose mass instead. Controlled Variables in this lab were: Composition of plastic cups, Brand of Russet Potatoes, Brand of Sweet Potatoes and the Temperature of the room. For independent variable that caused the results recorded it was the different Sucrose concentrations (0.0M, 0.2M, 0.4M, 0.6M, 0.8M, 1M). The dependent variable was the percentage change from the initial weighs to the final. The cup with .4 molarity was the closest to an isotonic solution and was used as the control group for the lab. Water potential is the free energy per mole of water. It is
Four eggs that were previously soaked in vinegar were placed into four beakers with different levels of a glucose solution. The four beakers were filled with distilled water, 0.5M glucose, 1.5M glucose and 2.0M glucose. After the eggs were placed in the solutions, they were left for 60 minutes but weighed every 15 minutes to record whether there was an increase or a decrease in mass. The various masses were recorded as well as the percent change in mass. These were then recorded as line graphs. From this it was able to be determined if the egg had been in a hypotonic, hypertonic or isotonic solution, thus being able to determine if osmosis had occurred.
The class data that was received supported the group members’ hypothesis that the rate of osmosis will increase if the sucrose concentration increases as well. The trend line that was received from the data also supported the hypothesis because it increased as the sucrose concentration increased. The initial weight gain percents were all different because all of the groups’ sugar concentrations were not completely identical. The method used wasn’t entirely accurate because there could’ve been some flaws such as some bags weren’t secured enough and might have leaked sucrose into the de-ionized water causing the results to be different. The bags might have not been washed thoroughly which could have ultimately allowed sucrose into the de-ionized water. The results could have been more accurate if the baggies were left in the
Six plastic cups were obtained and labeled 0.2 M, 0.4 M, 0.6 M, 0.8 M, and 1.0 M. Next, each of the six dialysis tubes were knotted on one end and filled with the sucrose samples, and then tied off. These samples were then dried by patting with a paper towel, weighed and placed into their corresponding cups. The mass of each sample was recorded in table 2 on the data sheet. Each cup was then
Osmosis is when water passes through a cell membrane, it is also form of a diffusion, which is a form of passive transport. Osmosis will continue to until an equilibrium is reached which is when the solutions are isotonic. This means that the solution has the same amount of solute on both sides. If the solution is hypertonic, it has more solute in the solution. In this situation water will move towards it. if the solution is hypotonic, it has less solute in the solution. Whereas in this situation, water will move out of the solution.