25 ml of diluted unknown acid solution to 100ml beaker by using 25 volumetric pipet. 10ml of deionized water and 3 drops of phenlpthalin indicator the beaker labeled as 3. Potentiometric titration acid solutions 125 ml of NaOH was obtaining in a beaker and 50 ml of NaOH transfer to buret the tip and the meniscus is at below 0 ml. one magnetic stirring bar placed in a beaker contain one of the known solution on a stir. The pH recorded by using pH electrode before adding NaOH.
Chemical Reactions: Investigation Problem: What is the effect of the temperature of the rate of a chemical reaction? Purpose: the rate of a chemical reaction is essentially how ‘fast’ the reaction is. In this investigation, we will be how temperature influences the rate of a reaction. Hypothesis: I believe that the higher the temperature (independent variable), the quick the reaction happens (dependant variable). I believe this will happen because the higher the temperature the more the particles vibrate making them mix with other particles.
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.
What should this contain? j Count up how many iodine drops you have used, each one equals 10 seconds of reaction time. k Repeat the whole procedure with another of the pH buffers or pool your results with others in your class. l Collect repeat data if there is time. m Plot a graph of time taken for starch to break down against pH.
After which time, 2.1 mL of 30% hydrogen peroxide was added slowly followed by sodium hydroxide until a pH of 8 was observed. 20 mL of H20 and 10 mL diethyl ether were added to the flask. The contents were separated and the aqueous layer was rinsed with four 10mL portions of ether followed by 15 mL of sodium bicarbonate. The ether layer was dried with granular magnesium sulfate and then the solvent was removed by evaporation under reduced pressure. Lastly, the final product was analyzed by mass spectrometry and HNMR.
Experiment Colligative Properties & Osmotic Pressure Karmin Currin 1/19/2014 1:00pm Abstract The purpose of this experiment is to understand and compare the difference of the freezing points between pure solvents in a solution and a non-volatile solute. Secondly, osmosis is demonstrated in a permeable membrane in this case a dialysis tubing and a less permeable membrane with a much harder shell like the egg. Experiment and Observation Starting with Part I of this experiment I gathered together all my items I needed. Small rubber band, salt, tap water, distilled water, 1/8 teaspoon measuring spoon, crushed ice, beaker 100 mL plastic, stopwatch-digital, test tube 13 x 100 mm, digital thermometer, well plate-24. First I made a water bath by filling the 100 mL beaker with cool tap water.
A melting point will be ran on the aspirin when completely dry. A capillary tube containing the dry aspirin will be placed into the melting-point apparatus. This process is to determine the melting point range of aspirin. First, a hot water bath was created with a 400. mL beaker on a hot plate. 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.
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.
This report includes measurements collected from graduated cylinders, balances, and metric rulers, and the densities the data helped calculate. Hypothesis Based on our study of density, we should be able to calculate the mass and volume of each of the seven objects to find their densities and then determine what each of the objects are using the calculated density. Materials and Methods At Lab Station 1, a dry 100mL graduated cylinder was placed on a balance and the mass was recorded in grams to the nearest .01 gram. Approximately 60mL of the Clear Liquid 1 was carefully poured into the graduated cylinder. The graduated cylinder was placed on the scale again (with the added liquid) and the mass was measured in grams to the nearest .01 gram.
OBJECTIVES In this experiment, you will • • • • Determine the freezing temperature of the pure solvent, lauric acid. Determine the freezing temperature of a mixture of lauric acid and benzoic acid. Calculate the freezing point depression of the mixture. Calculate the molecular weight of benzoic acid. Figure 1 MATERIALS Data Collection Mechanism Temperature Probe ring stand 400 mL beaker Tissue or paper towels lauric acid, CH3(CH2)10COOH lauric acid-benzoic acid mixture hot water bath utility clamp two 18 × 150 mm test tubes (if pre-made samples are not provided by your teacher) 1 “The Computer-Based Laboratory”, Journal of Chemical Education: Software, 1988, Vol.1A, No.