Objective The purpose of this lab was to demonstrate and view the osmotic process without using a microscope or chemical testing. In order to do so, background knowledge on the direction and flow of water is needed to identify the movement of osmosis. Hypothesis The hypotonic solution will cause the potato strip to become heavier relative to its previous mass, the hypertonic solution will cause a decrease in the potato strip’s mass, and the isotonic solution will result in no change in mass. Pre-Lab Questions Why is it so important not to eat or drink anything in the lab? It is important not to eat and/or drink anything in the lab because often times, many chemicals are clear, colourless and odourless.
The rate of diffusion of a substance is proportional to the concentration gradient of that substance (Leaist). In the experiment there were 4 different test groups: the control (tap water in tap water), 20% fructose in tap water, 40% fructose in tap water, and tap water in 20% fructose.
4.Literature research: Osmosis is the spontaneous net movement of solvent molecules through a semi-permeable membrane into a region of high solute concentration, in the direction that tends to equalize the solute concentrations on two sides. There are 3 types of osmotic conditions that affect living cells, they are: hypertonic, hypotonic and isotonic states. These terms describe the osmotic state of the solution that surrounds a cell, not the solution inside the cell. Hypertonic conditions cause water to diffuse out of the cell, making the cell shrivel. Hypotonic conditions cause water to move into the cell swelling or bursting it.
When the temperature becomes low, the cell membrane is less absorbent and does not permit more substance to pass through the membrane. My results supported my hypothesis which was as the temperature increases so does the beets permeability. In this experiment, there is a human error, as we cut the beet the measurement is near each other but not perfect. The amount of water in each tube would also be a reason for an error in this lab because it was not all equal. Another factor would be, temperature because some were long and some were short.
Advection describes the movement of the contaminant due to a pressure gradient, and, in the subsurface, the mass flux is proportional to the flow velocity, contaminant concentration, and the effective porosity of the media [Fetter 1999]. Dispersion is the scattering, spreading, and/or mixing of the contaminant as a result of variations in micro-scale flow velocities. It should be noted that when a contaminant is flowing in a horizontal direction, the amount of dispersion could be quite different in the concurrent (longitudinal) direction compared to a direction that is perpendicular (transverse) to the direction of flow. Lastly, diffusion refers to the migration of the contaminant in response to a concentration gradient. As a result of diffusion, contaminants migrate from regions of high concentration to regions of low concentration.
The driving force of diffusion is the concentration gradient. There is a wide range of diffusivities for the various dopant species, which depend on how easy the respective dopant impurity can move through the material. Diffusion is applied to anneal the crystal defects after ion implantation or to introduce dopant atoms into silicon from a chemical vapor source. In the last case the diffusion time and temperature determine the depth of dopant penetration. Diffusion is used to form the source, drain, and channel regions in a MOS transistor.
Yara Mneimneh Ms. Nasrin Vali Biology 11 B 9. October. 2016 Osmosis Investigation Introduction Osmosis is the passive movement of water molecules across a selectively permeable membrane, from a region of low solute concentration to a region of high solute concentration. Osmosis is different than diffusion, since the net movement of the water is due to the solute concentration rather than the molecules. In this experiment, two types of solutions will be tested to examine the effect on osmolarity.
Introductions Osmosis is the process in which a molecules move from a high concentration to a low concentration, through a semi-permeable membrane separating the two substances. The flow of the solvent stops when both solutions become equal . Osmosis is a type one of the many different types of diffusion. In this investigation we testing which solute will have concentrations equal on both sides or whether or not it will be higher or lower. The two main passive diffusion and facilitated diffusion.
Diffusion and dissolution are two important process in chemistry, diffusion is process resulting from random motion of molecules by which there is a net flow of matter from a region of high concentration to a region of low concentration. A familiar example is the perfume of a flower that quickly permeates the still air of a room, If this movement is from one element to another e.g. Cu to Ni, then it is termed inter-diffusion. If the movement is within similar atoms as in pure metals, it is termed self-diffusion,Dissolution rate is defined as the amount of solid substance that reaches into solution per unit time,PROCESs OF DISSOLUTION The process of dissolution involves breaking of intermolecular bonds in the solute, the separation of the molecules of the solvent to provide space in the solvent for the solute, and the interaction between the solvent and solute molecule or ion. factors Affecting the Rate of Diffusion and dissolution: 1-Temperature: It takes a specific amount of vitality should get particles moving.
Now, imagine that we have combined the results from eight different laboratories in which everything was identical, except for the positions of the thermocouples in the water. In this case, each laboratory would report a different time of freezing. These differences were a major barrier to obtaining reproducible results during the early phase of this study. A difference in position of only a few millimeters can be significant depending on the size of the container”