b. Once again, place assembly in water bath and begin to heat c. When acetamide has begun to melt, record the temperature. d. Let assembly cool down and record temperature when acetamide begins to recrystallize. e. Repeat process two more times. Data: Data Table 1 | | | Rubbing Alcohol Trial # | Boiling Point | Percent Error | 1 | 79.5 C | 3.52% | 2 | 84.0 C | 1.90% | 3 | 83.5 C | 1.30% | Data Table 2 | | | | Acetamide Trial # | Melting Point | Freezing Point | Percent Error (Melting Point) | 1 | 79.5 C | 57.5 C | 3.50% | 2 | 80.5 C | 59.5 C | 0.60% | 3 | 78.0 C | 61.0 C | 3.70% | Observations: It was observed that thermometer placement could affect the readings in the water bath.
Then weigh the crucible without the hydrate after heating. Record both masses. Next, add CoCl2 ∙6H2O and weigh the crucible. Now place the hydrate and crucible on the hot plate. Observe the color change while it is being heated.
The following data were obtained when a sample of barium chloride hydrate was analyzed as described in the Procedure section. Calculate (a) the mass of the hydrate, (b) the mass of water lost during heating, and (c) the percent water in the hydrate. Mass of empty test tube 18.42 g Mass of test tube and hydrate (before heating) 20.75 g Mass of test tube and anhydrous salt (after heating) 20.41 g. Mass of the Hydrate is 2.33g. Loss (H2O) is 0.34g. Percent H2O in Hydrate is equal 0.34/2.33=14.6% 3.
10/8/13 Lab Report Introduction The purpose of the experiment was to do three different reaction and calculate the enthalpy change of the reaction with Hess’s Law. Then compare your calculated results to the results from the experiment. Experimental Design Materials: Vernier computer interface Computer Temperature Probe Two styrofoam cup 100 mL graduated cylinders Glass stirring rod 2.0 M Hydrochloric acid, HCl, solution 2.0 M Sodium Hydroxide, NaOH, solution 2.0 M Ammonium Chloride, NH4Cl, solution 2.0 M Ammonia, NH3, solution Ring Stand Utility Clamp Fume hood or well-ventilated room Magnetic Stirrer Paper Lid Procedures: Use proper lab safety and wear safety glasses, and make sure in well-ventilated room. Connect the temperature probe to the Vernier interface in the Channel 1 port. Then connect interface to the computer using the USB cable.
Press CALIBRATE enter 0.0C when promted press ENTER insert temperature probe and swirl it around until the screen reads 0.0C press ENTER 5. Remove temperature probe 6. Press SETUP F1 a. Set max temperature to 70-75C b. Set min temperature to 15-18C c. Time should range from 0-250 seconds 7.
Obtain an Erlenmeyer flask that has a vacuum opening and attach the vacuum tube to it 8. Insert funnel and rinse the funnel with distilled water 9. Turn vacuum on and pour the pink solution into the Erlenmeyer flask, the precipitate should stay on top of the filter 10. Rinse the beaker out until all residue is gone 11. Try to rinse the precipitate in the funnel until the pink color is gone 12.
Lab Report: Crystallization of phthalic acid from water (microscale) Abstract The 0.60 g of phthalic acid is put in a water solution, which is brought to a boil to dissolve the acid into water. After the solution was clear with just the rock visible the test tube solution is now cooled in ice and stirred till crystals appear. Excess water is then removed, then the adding of ethanol is done to separate the water from the crystals. Tube is then placed in a beaker of hot water which aids in the removal of the solvent. After drying the compound the percent recovery was found to be 70%.
After all the acid has been completely added and the reaction has stopped, use a pipette to add a few extra drops of acid into the beaker until the reaction stops. 7. Place the beaker on a hot plate and heat on a high setting to boil off the water. WARNING: THERE WILL BE A SMALL AMOUNT OF HYDROCHLORIC ACID BOILING OF THE MIXTURE. DO NOT PLACE YOUR FACE DIRECTLY ABOVE THE BEAKER.
3 x (C H5 N) = C3H15N3 Hydrated compounds Solving process: 1st- the difference between the initial mass and that of the dry sample is the mass of water that was driven off. Mass of hydrate minus mass of dry sample equals the mass of water 10.407 – 9.520 = 0.887 g 2nd- The mass of dry BaI2 and the mass of water are converted to MOLES. 9.520 g BaI2 x 1 mol BaI2 ∕ 391 g BaI2 = 0.0243 mol BaI2 anhydrate 0.887 g H2O x 1 mol H2O / 18.0 g H2O = o.o493 mol H2O 3rd: Dividing both results by the amt of 0.0243 mol, we get a ratio of 1 to 2.03, or 1 to 2, since the formula must have full numerical integers of water molecules, in other words no fractions of a water molecule. Thus, for every 1 mole of BaI2, there are two moles of water. The formula for the hydrate is written as BaI2 • 2H2O And it is named barium iodide dihydrate.
baking soda) will be mixed with acetic acid (HC2H3O2, a.k.a. vinegar) to generate sodium acetate (NaC2H3O2) and carbonic acid (H2CO3). The carbonic acid will rapidly decompose to generate gaseous carbon dioxide and liquid water. You will calculate your theoretical yield of NaC2H3O2 For this reaction, we will need to use 0.025 moles of NaHCO3. Procedure: 1.