Fill the calorimeter cup approximately 2/3 with distilled water at room temperature and record the mass in Data Table 1 5. Measure the temperature of the tap water in the calorimeter cup and record in Data Table 2. 6. Carefully transfer the metal to the beaker with boiling water. Boil at least 10 minutes.
After sitting for 30minutes this solution stayed the same color. Table 2: Solution Colors Before 30 Minutes of Sitting in a Beaker of Water and After Benedict’s test Solution Content | Initial color | Final color | 15% glucose1% starch | Cloudy | Orange | Distilled water | Clear | Blue | This table shows the colors of the solutions before sitting for 30minutes in the solution of water and IKI and the final color after the Benedict’s test has been performed on the solution. The initial color of the 15% glucose and the 1% starch before sitting in the beaker solution for 30 minutes and before the Benedict’s test was perform was a cloudy white color. After the Benedict’s test was performed on this solution it turned an orange color. The solution in the beaker which was distilled water was clear before the IKI was added and before the dialysis tubing was placed in it.
Observe the color change. Osmosis: The materials needed for the osmosis experiment include: 1%, 20%, and 40% sucrose solutions, a 100ml beaker, pipettes, 3 dialysis bags/tubing, scales, and weigh boats. The procedure was a follows; Place the 1% sucrose solution into a beaker. Next, fill one dialysis bag with 1% sucrose
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.
I inserted the digital thermometer into the test tube and took reading every 30 seconds until the readings remained constant. The readings for the distilled water did not change. I then placed the test tube in the beaker’s ice water bath and set the stopwatch at zero. I carefully stirred the water in the test tube with the thermometer and recorded the temperature of the water at 30-second intervals. Data Table 1: Pure Water Time in seconds | Distilled H2O Room Temp | Distilled H2O Ice bath | 0 | 2431o C | 24.3o C | 30 | | 4.8o C | 60 | | 0.7o C | 90 | | -0.4o C | 120 | | -0.8o C | 150 | | -.10o C | 180 | | -.10o C | Data Table 2: Salt Solution Time in seconds | Salt Water Room Temp | Saltwater Ice Bath | 0 | 20.8O C | 14.2o C | 30 | | 3.0o C | 60 | | 0.2o C | 90 | | -0.3o C |
Introduction Osmosis is the diffusion across a semi-permeable membrane. It works by moving the water molecules to different places with a lower concentration until it reaches equilibrium. Osmosis is moving water molecules from an area with high concentration to an area with low concentration through a partially permeable membrane. without osmosis, our cells would die do to lack of water, but osmosis allows water to enter through diffusion. in this lab, there is an observation of a demonstration of osmosis, prediction of how various factors affect the rate of osmosis, and interpretation of data about osmosis.
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.
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.