The 15 M NH4OH was added drop wise until a color change occurred, or until 20 drops were added. An additional 10 drops of 15 M NH4OH were then added to each solution. Again, 5 centrifuge tubes were labeled for the same 5 cations and 20 drops of each solution were added to the appropriate centrifuge. HCl was also added to a 50 mL beaker. The Nichrome wire loop was dipped in the HCl solution and placed over the Bunsen burner to disinfect it.
Diffusion and Osmosis Lab Part 1A: Diffusion Evidence: Table 1: The Color of Different Solutions Before and After Diffusion for 30 Minutes Content | Initial Solution Color | Final Solution Color | Bag15% glucose1%starch | Cloudy white | Very dark purple | BeakerWater + IKI | Golden yellow | Golden yellow | The above table represents the final and initial colors of the solution that was inside of the dialysis tubing and the solution that was in the beaker. A 15% glucose and 1% starch solution was placed inside of the dialysis tubing. The initial color of the solution in the bag was a cloudy white but after 30 minutes of sitting in the beaker of water and IKI the color turned a very dark purple almost black. Inside of the beaker was a water and IKI solution. After sitting for 30minutes this solution stayed the same color.
With increasing temperatures the solute can be dissolved by a solvent during recrystallization. Experimental section Preparation of Chalcone To prepare chalcone 2.1mL of NaOH in was dissolved in 40mL of water and about 25mL of ethanol was added in a 125mL Erlenmeyer flask as soon as pellets were dissolved. Then 0.080 mole of acetophenone was stirred into the 125 mL flask, then place into an ice bath. At once 0.080 moles of bezaldehyde was added to the mixture and stirred all the while temperature was kept between 20-30°C. A stopper was placed on the flask while the mixture was stirring with stirrer for 11/2 hours.
The controlled variables is the numbers of beans, timed every 5 min for all respirometers. 5. I want to see your processed data table and I want to see the graph of oxygen use for your mung beans both in the ice bath and they in regular temperature. Use corrected values. Key: respiration rate/ temperature Table 1 | ml/ 5minutes | Ml/5minutes | Ml/minutes | Ml/5 minutes | Time | Room temperature bean | Room temperature glass | Cold temperature bean | Cold temperature glass | Initial | 6.1/25 | 8.2/25 | 8.2/11 | 7.5/11 | 5 | 6/24 | 8/24 | 8/11 | 7.3/11 | 10 | 5.8/24 | 8.2/24 | 8.2/10 | 7.5/10 | 15 | 4.7/24 | 8.2/24 | 3.1/10 | 4.9/10 | 20 | 4.3/24 | 8/24 | 3/10 | 5/10 | 25 | 3.1/24 | 7.9/24 | 2.9/10 | 5.1/10 | 30 | 2/24 | 7.8/24 | 2.9/10 | 5.4/10 | Table 2 | ml/ 5minutes | Ml/5minutes | Ml/minutes | Ml/5 minutes | Time | Room temperature bean | Room temperature glass | Cold temperature bean | Cold temperature glass | Initial | 3.9/25 | 1.8/25 | 1.8/11 | 2.5/11 | 5 | 4/24 | 2/24 | 2/11
While the water was sitting, I put each portion of beet into individual beakers and began to test each portion individually. For tests 1-4 I soaked each piece of beet in water warmed to it’s corresponding temperature for one minute. I then removed the beet from the water and placed it back into its beaker then added 3ml of the room temperature tap water. I then let it sit for 20 minutes. For test 5, I placed the dry beet in its beaker and put it into the refrigerator for 30 minutes, removed it, and added 3ml room temperature tap
Once dry, 2.2 mL of styrene were added to the round bottom flask, and an ice bath and mechanical stirrer were placed under the reaction vessel. A total of 6.2 ML of 1.0M BH3-THF were added to the reaction vessel slowly by a syringe. This addition took place over a 30 minute time period. The vessel was then left alone for 50 minutes. After which time, 2.1 mL of 30% hydrogen peroxide was added slowly followed by sodium hydroxide until a pH of 8 was observed.
The temperature was raised to 70 degrees Celsius and 4.419 g of salicylic acid was measured out on a balance and transferred into a 125. mL Erlenmeyer flask. Next, 8.00 mL of acetic anhydride was measured out and poured into the flask containing salicylic acid, ten drops of phosphoric acid was placed inside. The flask was then immersed into the hot water bath for twenty minutes. A vacuum filtration system was set up and the contents of the flask was transferred onto the filter paper. The mass of the filter paper and watch glass was 42.7131 grams.
The pH recorded by using pH electrode before adding NaOH. The solution titrated by 2 ml of NaOH each time and the pH recorded until the color change. These steps were done for the two known solutions and the unknown solution. Part 2 10 ml of vinegar placed in 100ml volumetric flask and deionized water added until the mark. The solution transferred in 150 ml beaker labeled as beaker #1.
Allow the crystals to dry for 1 week then, weigh it, take a MP, and calculate the % yield. * Assemble the apparatus for reflux using the diagram (see figure 1), place boiling chips or a stirring bar in the bottom of the flask. * Weigh 2grams of finely ground nutmeg and combine with 10ml of diethyl ether in a 50ml round bottom flask. * Place a heating mantle under the round bottom, turned on and the heat was slowly adjusted until the mixture starts to boil for 45minutes, then let cool to room temperature by sitting it on the lab bench. * Pour a little ether over the nutmeg residue on the filter paper so that any Diethyl ethanol traces clinging to it is washed down and mixed with the filtered liquid underneath.
First, 0.4040 grams of NaH2PO4 and 0.3989 grams of Na2HPO4 were added to a 150 mL beaker, along with 50 mL of distilled water. Next, 20 drops of bromothymol blue were inserted into the solution. The program LoggerPro and a Vernier pH probe were used to calculate the pH. Then, a volumetric flask was used to measure 5 mL of the buffer solution into each of three, separate 50 mL beakers. After rinsing a volumetric pipet with 1.0 M HCl, 1.00 mL of 1.0 M HCl was transferred to one of the three beakers.