Concentration

Phosphate can be harmful when excessive amount is present in the drinking water system. The U.S. Public Health Service has set the maximum value of phosphate in drinking water at 3.0 mg/L. In this experiment, several samples were diluted and its concentration were analyzed through a spectrophotometer. The results obtained (0.1 mg/L and 2.28mg/L) are within the U.S. Public Health Service’s standards and are deemed to be safe. Introduction It is important that drinking water is monitored regularly…

This gave us a differentially permeable membrane so that we can observe osmosis and what happens when the membrane is presented with different solutions. Since we did not know the concentration of the egg, we had to assume that it equaled the concentration of the membrane. We then had the ability to determine the concentration based off the assumption and the rate of osmosis. We used 5 different sucrose solutions: 0%, 10%, 20%, 30%, and 40%. One group had an ‘Unknown’ sucrose solution, this…

absorbance (atomic absorption) in function of the strontium concentration and it can clearly be seen in figure 2 that at concentrations above 10 ppm the samples start to present non-linear absorption. Therefore, all the strontium quantifications were performed working with concentration below 10 ppm and appropriated dilutions were done when it was necessary. The quantification limit was found to be 0.2 ppm and therefore any concentration below this limit cannot be quantified. Figure 2.…

water from an area of lower solute concentration to an area of higher solute concentration, in order to reach a dynamic equilibrium. The three general states of tonicity are hypo-tonic, iso-tonic, and hyper-tonic. Hypotonic solutions are lower in concentration as compared to another solution. There will be a net movement of water into the solution with higher solute concentration. If we take the example of a cell culture, pure water has a lower solute concentration than the inside of the cell so…

we can see the effects when we placed the egg either in a hypertonic or hypotonic solution. Since the egg membrane is semipermeable similar to the cell membrane, it only allows specific substances to pass in and out of the egg membrane down its concentration gradient. In this case, we are trying to measure to the diffusion of water that goes in and out of the egg membrane. This is also known as osmosis. We performed the experiment by placing the egg into two different solutions, the corn syrup…

membrane from a high concentration area to a low concentration area without any forces acting upon the substance. Facilitated diffusion is a passive diffusion process involving the transportation of large or polar molecules and ions across the cell membrane (which they cannot normally pass through) with the help of transport proteins. Because facilitated diffusion is a form of passive transport, no energy is required for the movement of a solute from a high solute concentration area to a low…

the molecules crossing, for more of an understanding according to Anita H, she says “…high water concentration to an area of low water concentration through a partially selectively permeable membrane” (Anita) The molecules cross from less concentrated solution to the higher concentration solutions (The low concentration solution is the distilled water immersing the dialysis bag and the concentration liquid is the fluid inside the bag). Throughout the experiment it is knowledgeable that invertase…

[Fe(H2O)6]+3(aq) + SCN-(aq)  [Fe(H2O)5(SCN)]+2(aq) + H2O[2]. However, because the concentration of water in the dilute aqueous solution is constant it can be written in the simple form of Fe+3(aq) + SCN-(aq)  Fe(SCN)+2(aq)[2]. In the experiment the stability constant was achieved by first creating a calibration curve. From the calibration curve data was taken and used in order to find the equilibrium concentrations, once that was found the stability constants were calculated with the…

conducted in order to determine the molarity of sucrose concentration where the mass of 2cm^3 of Classic Russet potato segments and pear segments does not change, representing an isotonic concentration. By calculating the change of mass of the potato segment and pear segments prior to being placed in the sucrose solution against the mass after being in the sucrose solution for 45 minutes. Our goal was to determine what type of osmotic concentration was created as compared to the potato and pear…

October 14th, 2015 Analysis of Consumer Products with Unknown Protein Concentrations Using Spectrophotometry Abstract Consumer products typically give detailed information about their ingredients and nutrients. However, the concentration of a specific nutrient may not always be clear from just the label information alone, and in some cases the product labels may not be accurate. Thus, it may be hard to compare the concentration level of a certain nutrient, such as protein, amongst different…