How Does The Concentration Affect The Rate Of Diffusion
The first lab will investigate the movement of glucose and starch across a selectively permeable membrane through a process of diffusion. The movement of a solute through this membrane is called dialysis . Diffusion is a form of passive transport. It is the movement of molecules from areas of higher concentration to those of lower concentration, until there is an even concentration. This movement is random because it is a result of kinetic energy. Diffusion is a slow process, but there are many factors that will affect it’s rate. The rate of diffusion will vary depending on the size of the particle. For example, a smaller particle will move faster than a large molecule at a given temperature . During reactions, when there is more energy, the reaction will take place at a faster rate. An increase in temperature will result in and increase in the amount of energy available, therefore the particle will move faster and the rate of diffusion will increase. Another factor affecting the rate of diffusing is the density of the substance being diffused. As the density of the substance becomes higher, the mass of each particle will also increase causing the reaction rate to become slower. Lastly, the
…show more content…
medium in which diffusion occurs in will also have an affect on the reaction rate. If the particles in the medium are large, more collisions will occur between them. This would cause the rate of diffusion to slow down.
Diffusion is the movement of particles from areas of high concentration to low concentration, meaning it flows with the concentration gradient.
This means that when there is a large difference in the concentrations, there are more effective collisions in the molecules resulting in an elevated reaction rate. All cells have a selectively permeable membrane. These membranes only allow certain molecules to pass through them by either passive or active transport. The dialysis bag being used in Lab 1A is an example of a selectively permeable membrane. Small molecules like water are able to move liberally across the membrane but larger molecules will take more time to pass through. The movement of molecules across this membrane, against the concentration gradient, is called
dialysis.
The four reactant molecules in this lab are water, glucose, starch, and iodine-potassium iodide (IKI). Water is a polar covalent molecule that is made up of one oxygen atom and two hydrogen atoms. Water is able to pass easily across selectively permeable cell membranes . Glucose is composed of six carbon atoms, twelve hydrogen atoms, and six oxygen atoms. It’s chemical formula is C6H12O6. It is a monosaccharide, meaning it is a simple sugar . Glucose is too large of a molecule to pass through cell membranes by diffusion, but is able to pass through the selectively permeable membrane by facilitated diffusion , a form of passive transport. Starch is composed of amylose and amylopectin . Starch is a very large molecule and is unable to pass across cell membranes. Iodine-potassium iodide is also known as IKI. It is a liquid compound that is used to detect starch in solutions. The molecules that make up IKI are larger than water molecules, but are still small enough to pass through cell membranes. IKI is composed of diatomic iodine and potassium. The iodines of the IKI compound are called triiodine. When IKI is added to a liquid solution, the color of the solution will change to blue when starch is present.
Glucose Testape is used to detect the presence of glucose in solutions. The strips have glucose oxidase, peroxidase and orthotolidine. Glucose oxidase catalyzes reactions by forming hydrogen peroxide and gluconic acid. Peroxide catalyzes the reaction between the hydrogen peroxide and the orthotolidine which produces a blue color. When the Testape is dipped in a solution, the darker the blue, the more glucose there is in the solution.
medium in which diffusion occurs in will also have an affect on the reaction rate. If the particles in the medium are large, more collisions will occur between them. This would cause the rate of diffusion to slow down.
Diffusion is the movement of particles from areas of high concentration to low concentration, meaning it flows with the concentration gradient.
This means that when there is a large difference in the concentrations, there are more effective collisions in the molecules resulting in an elevated reaction rate. All cells have a selectively permeable membrane. These membranes only allow certain molecules to pass through them by either passive or active transport. The dialysis bag being used in Lab 1A is an example of a selectively permeable membrane. Small molecules like water are able to move liberally across the membrane but larger molecules will take more time to pass through. The movement of molecules across this membrane, against the concentration gradient, is called
dialysis.
The four reactant molecules in this lab are water, glucose, starch, and iodine-potassium iodide (IKI). Water is a polar covalent molecule that is made up of one oxygen atom and two hydrogen atoms. Water is able to pass easily across selectively permeable cell membranes . Glucose is composed of six carbon atoms, twelve hydrogen atoms, and six oxygen atoms. It’s chemical formula is C6H12O6. It is a monosaccharide, meaning it is a simple sugar . Glucose is too large of a molecule to pass through cell membranes by diffusion, but is able to pass through the selectively permeable membrane by facilitated diffusion , a form of passive transport. Starch is composed of amylose and amylopectin . Starch is a very large molecule and is unable to pass across cell membranes. Iodine-potassium iodide is also known as IKI. It is a liquid compound that is used to detect starch in solutions. The molecules that make up IKI are larger than water molecules, but are still small enough to pass through cell membranes. IKI is composed of diatomic iodine and potassium. The iodines of the IKI compound are called triiodine. When IKI is added to a liquid solution, the color of the solution will change to blue when starch is present.
Glucose Testape is used to detect the presence of glucose in solutions. The strips have glucose oxidase, peroxidase and orthotolidine. Glucose oxidase catalyzes reactions by forming hydrogen peroxide and gluconic acid. Peroxide catalyzes the reaction between the hydrogen peroxide and the orthotolidine which produces a blue color. When the Testape is dipped in a solution, the darker the blue, the more glucose there is in the solution.