Centrifugation: Acetic Acid and Centrifuge Tube

One gram of liver was sliced into pieces, then 10ml of homogenization buffer was added to it. The mixture of the liver and homogenization buffer was then placed into a homogenizer to make the liquid slurry. Once the slurry was made it was placed into a 50ml falcon tube to then be placed in the centrifuge. The slurry was centrifuged for 2 minutes at 2000rpm. Once the spin in the centrifuge was complete, the slurry had separated, the most dense particles to the bottom of the tube forming sediment and the lighter (liver succinate dehydrogenase enzyme) also known as the supernatant. The supernatant was extracted from the falcon tube and placed into a test tube. The tube was then kept at a low temperature, (in an ice bath) until it was required for use.

A centrifuge is a laboratory device that is used for the separation of fluids, gas or liquid, based on density. If you open a centrifuge and you notice that a sample has broken, close the lid immediately and leave the centrifuge closed for at least 30 minutes. This allows aerosols to settle and lowers your risk of inhaling any harmful aerosols released from the broken samples. Broken tubes, even plastic ones, can be sharp so you want to avoid cutting yourself, so you could use gloves to protect your hands from getting cut.

solids and liquids that were in the solution. The centrifuge was able to do this

Me and my lab partner, obtained a mixture of a un known proportion from the instructor and then flow the guide line in our lab manual to separate the mixture by applying the separation method motioned in our lab manual pages 33-40 . In this experiment, the separation methods were decantation,

This experiment was done in order to understand both fractional distillations and gas chromatography. In addition, this experiment was done to separate and identify two liquids that made up an unknown mixture. Gas chromatography was used to figure out the ratio of these two liquids.

The purpose of this separation of a mixture lab is to give students the challenge of figuring out how to separate a provided mixture, and following through with their procedure. The mixture is composed of salt, sand, poppy seeds, and iron filings, and all of these components should be separated and dried as well as possible by the end of the lab.

The molarity of the solutions in each dialysis bag, and the percent change in mass are both included to best show effect of increasing molarities of sucrose and osmosis. The percent change in mass exhibits the process of osmosis, because osmosis must take place for water molecules to transfer from one side of the semi-permeable (in the surrounding distilled cup) to another (within the dialysis tubing), in order to reach equilibrium.

More specifically for the experiment we will need four deshelled eggs, four beakers and distilled water with a certain percentage of sucrose, a timer, and a scale to weigh the eggs. Using the process of osmosis, we will determine the weight of the eggs after being soaked in the solution. The four beakers each had distilled water in them with sucrose but all contained different amounts. One beaker contained 0% sucrose. The other beakers contained 10%, 40%, and an “unknown” amount of sucrose. Before placing the eggs into the solution, we are to weigh each egg separately to the nearest 0.1g and record this in table. Once that step has been completed, we then place one egg in each of the beakers separately that was marked with the amounts of sucrose. At fifteen-minute intervals, remove the deshelled egg from the water inside the beaker and wipe off all the excess water. After that process has been completed, we will weigh each egg separately to see if they have gained or lost their mass/weight. Once each egg has been weighed accurately, the recorded data is placed in the table provided. This step goes on for an hour. The deshelled eggs in this experiment will increase in mass in the different types of distilled water. This lab session provided the class with the evidence that diffusion and osmosis occurs within the different types of solutions.

each  anion solution into  a centrifuge tube.   The tubes  were labeled accordingly.  The original color of

100 mL of whole milk was measured in 250 mL flask and put on a hot plate in the hood. A thermostat was used to make sure that the milk did not go over 40 ͦC. When the Milk reached 39.2 ͦC, 11.0 mL of 10% acetate acid solution was added and stirred form 1 minute. Three coffee filters were nested into one another and used with a funnel to filter the solution into a clean 250 mL flask. A vacuum filter was set up while the solution was

As the dilution factor increased for both the raw milk (unpasteurized) and pasteurized milk samples, the number of colonies decreased. The number of cells/mL in the pasteurized milk sample is considerably less than the number of cells/mL in the raw milk sample.

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.

Chromatography is a separation technique in which the mixture to be separated is dissolved in a solvent and the resulting solution, often called the mobile phase, is then passed through or over another material, the stationary phase. The separation of the original mixture depends on how strongly each component is attracted to the stationary phase. Substances that are attracted strongly to the stationary phase will be retarded and not move alone with the mobile phase. Weakly attracted substances will move more rapidly with the mobile phase.

Quantitative analysis is the determination of an amount present in a variety of settings. On the other hand, qualitative analysis is the determination of non-numerical information about a reaction, such as observing that a reaction results in a color change. There are chemical changes that separate cations and physical separations, such as decanting, where liquid is poured from a solid-liquid mixture, leaving the solid behind. Centrifuging is another separation technique, where a solid is separated from a liquid by whirling the mixture at high speed. A mixture of metal ions in a solution can be separated by a reaction of precipitation and in this experiment, the metal cations of aluminum, nickel, and iron ions will be separated from a solution

3. McMurry, John C., Robert C. Fay, and Stephanie Dillon. Experiment 3: Separation of the components of a mixture. Chemistry: Laboratory Manual. 6th ed. Boston: Prentice Hall, 2012. 33-42.