Semipermeable membrane

The forward osmosis (FO) process is an emerging separation/desalination process. It is rapid process compared to other membrane processes such as reverse osmosis. The physical phenomenon of forward osmosis (FO) can demonstrated as the motion of water molecules through a semi-permeable membrane due to difference in osmotic pressure driving force through the membrane. The membrane enables only water molecules to pass through when salt molecules are rejected. The forward desalination technique makes use of a draw solution with high osmotic pressure to draw the water molecules from a inlet solution such as brackish with lower osmotic pressure in contrast to the draw solution. As illustrated in Figure 1, water flux directions in forward osmosis and reverse osmosis. In forward osmosis, the inlet solution of high water chemical potential is separated from the draw solution of low water chemical potential by a semipermeable membrane (as shown in figure 1 (a)). Figure 1 (b) shows water molecules are transported from the inlet to the draw solution in FO because of the difference in osmotic pressures. However, in reverse osmosis (figure 1 (c)), hydraulic pressure is applied to the inlet to overcome the osmotic pressure. The application of…

Our guiding question was: How does the concentration of salt in water affect the rate of osmosis? Osmosis is the spontaneous net movement of solvent molecules through a semipermeable membrane into a region of higher solute concentration, in the direction that tends to equalize the solute concentrations on the two sides. Osmosis also refers specifically to the diffusion of water molecules. Diffusion is the movement of chemical particles for an area of high concentration to an area of low…

Group 8 Con. of saline Initial Mass (g) Final Mass (g) Initial Mass (g) Final Mass (g) DH2O 20.01 17.76 16.9 16.6 0.2% 19.19 18.79 19.0 18.6 0.45% 19.83 18.03 17.9 16.7 0.85% 19.30 16.39 19.3 18.3 3.5% 19.85 18.05 17.1 18.1 10% 16.53 16.80 17.5 18.8 Processed Data: Average Mass Difference Percent Change Concentration of saline Initial Mass (g) Final Mass (g) (g) % DH2O 137.9 129.43 -8.47 -6.14% 0.2% 135.55 130.72 -4.83 -3.56% 0.45% 138.91 131.07 -7.84 -5.64% 0.85% 145.83 138.27 -7.56…

Analyzing Various Permeable Bags Placed in Different Concentrations of Water and Sucrose Introduction Osmosis is defined as the movement of water from a region of water that has a higher potential to a region of water that has a lower potential through semipermeable membranes. There are three types of solutions, hypertonic, hypotonic, and isotonic. Hypertonic solutions have a higher concentration of solute while hypotonic solutions have a lower concentration of solute. Isotonic solutions have…

In this lab the dialysis was used for the diffusion and osmosis of iodine, glucose, starch and water. However, starch was unable to pass through the membrane due to it being too large. This is where it does not fully resemble a cell membrane because it can not transform and undergo things such as endocytosis to allow all the molecules to pass through. Conclusion This lab provided a good perspective of the movement of molecules diffusing and going through osmosis into a cell. The ability of the…

Introduction The experiment will be working with diffusion and osmosis; it will test if the starch will travel through the semi permeable membrane (dialysis tube) causing osmosis. Diffusion is when a substance is highly concentrated turns into a lower concentration, and is evenly distributed throughout. An example of diffusion is when you cook and the smell of food flows until it in dynamic equilibrium; which is the even distribution of the substance. Osmosis is the movement through a semi…

Particles can move. One type of movement is diffusion. Diffusion is when particles move from an area of higher concentration to an area of lower concentration. The particles can move throughout a liquid, an area , or through a semipermeable membrane. Diffusion can be facilitated or non facilitated. When no other factors are involved in diffusion the particles are moving down their concentration gradient so that the amount of particles can be evenly distributed. if proteins or helpers are…

Observing the Effects of Osmosis on Model Cells of Different Sucrose Concentrations Cells are the building block of life. But these cells aren’t a closed system. There is a constant movement of various molecules in and out of the cell that brings nutrients in and brings waste out. This movement of particles in and out of cells is based around osmosis. It is written in the Lab Manual (2014) “Osmosis is diffusion of water across a differentially permeable membrane” (p. 97). In this experiment,…

THE EFFECTS OF OSMOSIS INTRODUCTION Osmosis is the process where molecules of a solvent are prone to pass through a semi-permeable membrane, going from a less concentrated solution to a higher concentrated solution. Doing this equalizes the concentrations on both sides of the membrane. Our question throughout the experiment was; What effects do the different concentrations of sucrose have on the rate of osmosis? The hypothesis was; If the solute concentrations do effect the rate of osmosis,…

Observing Osmosis INTRODUCTION Osmosis is the “diffusion of water across a selectively permeable membrane” (Raven et al. G-16). In this experiment, dialysis tubing was used to mimic the selectively permeable membrane to show what osmosis does when placed in different solutes. We filled dialysis tubes fill with different percentages of solute and placed them in beakers full of a different solute. Through this experiment, I saw what happens when the solution becomes hypertonic, hypotonic, and…