After that, dissolve the sample in 2 mL of deionized water and shake the test tube for 1 to 1 ½ minutes to dissolve the solid. Place another dry test tube in a 50mL beaker and weigh it. Find a bottle of barium iodide and record the name and molar mass. Then, weight out either anhydrous barium iodide or barium iodide dehydrate into this test tube and dissolve is it in 2 mL of deionized water. Pour the contents of one of the test tubes into the other and a reaction should occur and you should see a white precipitate of barium sulfate form.
Using a measuring cylinder, add 50cm3 of 1.0mol dm-3 sulphuric(VI) acid to the thyme extract in the conical flask. 8. Titrate the solution in the conical flask with the potassium manganate(VII) solution until a pale pink colour persists for 10 seconds. 9. Repeat the titration until there are two titres within 0.1cm3 of each other.
Abstract The focus of this experiment was to analyze the kinetics of a nucleophilic substitution. A mixture of 0.3622-M 1-bromopropane and 0.3622-M potassium hydroxide in an 90:10 ethanol/water solvent provided the reactants for a SN2 reaction to occur in a temperature controlled bath at 50.0˚C. The disappearing reactant was found by titrating timed aliquots during the reaction and then measuring the concentration of hydroxide. The k-value was found to be 0.0202 M-1Min-1. Using the linear form of the Arrhenius equation the activation energy was calculated to be 19.9 kcal/mol.
Measure the time it takes to completely dissolve. Record time in data table. Cold Water: Fill beaker with 80mL if ice water. Use thermometer to record temperature of water. Record the temperature.
Do an initial Benedict's test on the 15% glucose/1% starch and the beaker solutions for glucose by putting some of the solution and a roughly equal amount of blue Benedict's solution in a test tube, placing the test tube in boiling water for 90 seconds, and observing whether or not the solution changes color from blue. 3. Form a bag out of dialysis tubing by tying off one end, putting in enough 15% glucose/1% starch solution to fill it halfway, and tying off the other end leaving the other half of the bag void of anything (even air). Write down the solution's color. 4.
Care must be taken when squeezing the pipet bulb on the filter pipet. Too much pressure might cause the filter to leak or fall off. Add about 2 mL of fresh tert-butyl methyl ether to the solid in the RB flask, warm briefly, let the solids settle for a minute, and pipet the liquid to the centrifuge tube as before. Again allow the solids to settle briefly in the centrifuge tube, then filter the liquid through the pressure filtration apparatus, into the same 25 mL Erlenmeyer flask. Doing a rinse such as this helps to ensure that any trimyristin that was left behind in the RB flask and centrifuge tube is not lost, thereby helping to ensure that
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 |
Then 5mL of HCl was added to copper to completely remove all traces of zinc. Once the bubbling had stopped, the rest of the liquid was decanted away from the copper. Then the copper recovery set up was put together using tubing, Buchner funnel, filter paper and suction flask. Then the filter paper was weighed before placing it in the funnel and wetted down. The aspirator was turned to medium high, and then the copper was poured onto wetted filter paper.
Obtain a clean-dry test tube. Place 0.3g of the unknown substance in the test tube. Next, add 10mL of distilled water to the test tube. Mix with a stirring rod until unknown is dissolved. 2.
Measure pure solvent 4. Add the solvent to the cyclohexane 5. Take the temperature of solution before submersion 6. Submerge the test tube in the ice bath and record the temperature every thirty seconds for nine minutes, recording the temperature the solution starts to freeze at. 7.