Method: 100 mL of water/ Isopropyl Alcohol were added to a 250 mL Earlenmeyer flask along with 15 drops of phenolphthalein. A buret was washed with soapy water and rinsed with 0.2 M NaOH. The buret was then filled to 0.00 mL. 2.00 mL of NaOH were added to the flask and it was placed into an ice-water bath.
In the first section, the Synthesis of Aspirin, salicylic acid was weight to be 3.029 grams using mass by difference since it was weighed on a 150 milliliter beaker. 9.23 milliliters of the acetic anhydride and 14 drops of 85 percent phosphoric acid were added to this beaker. A Bunsen burner provided by the laboratory was then used to boil the just mixed combination by producing a flame underneath the positioned beaker on top, and then allowed to cool for several minutes after the Bunsen burner flame was terminated. Two quantities of distilled water were then added to this mixture to make it cool even further, which were 41 drops and 30 milliliters. After cooling for some time, this beaker was placed into an ice bath in order to start the crystallization process. A glass rod was used to scratch around the bottom and the sides to catch all of the crystallized Aspirin that was being formed during this whole process. Then, by using a Buchner funnel and filter paper, which was placed on top of the flask connected to a water aspirator with rubber tubing, the excess liquid was removed from the just scraped Aspirin crystals when the Aspirin was placed on the filter paper. Using a medicine dropper, the Aspirin crystals on the filter paper were washed with distilled water just so that any non-pure substances were removed from the crude product. When these crystals were then ultimately dry, they were placed on a watch glass and put into an oven for 30 minutes. Then they were weighed by mass by difference to yield 2.4667 grams of crude s...
Firstly, an amount of 40.90 g of NaCl was weighed using electronic balance (Adventurer™, Ohaus) and later was placed in a 500 ml beaker. Then, 6.05 g of Tris base, followed by 10.00 g of CTAB and 3.70 g of EDTA were added into the beaker. After that, 400 ml of sterilized distilled water, sdH2O was poured into the beaker to dissolve the substances. Then, the solution was stirred using the magnetic stirrer until the solution become crystal clear for about 3 hours on a hotplate stirrer (Lab Tech® LMS-1003). After the solution become clear, it was cool down to room temperature. Later, the solution was poured into 500 ml sterilized bottle. The bottle then was fully wrapped with aluminium foil to avoid from light. Next, 1 mL of 2-mercaptoethanol-β-mercapto was added into fully covered bottle. Lastly, the volume of the solution in the bottle was added with sdH2O until it reaches 500 ml. The bottle was labelled accordingly and was stored on chemical working bench.
However, the increased temperature of the new acid solution was at a greater temperature than the ambient temperature and the temperature of the water. This suggests that some of the results obtained were partially due to the fact that some of the heat energy of the acid was transferred to the water, as well as the hydration of ions present in solution. An improvement would be to create the solutions of desired concentration and allow them to reach thermal equilibrium with the surroundings. This would allow more accurate results and the allow for the assumption that the temperature change observed during the experiment would only be due to hydration of
This was allowed to mix for a few minutes; a little excess water was used to ensure that sodium bromide was fully dissolved. This mixture was placed in an ice bath while continuing to stir. 1.3 ml (24.39 mmols) of concentrated sulfuric acid was added dropwise. The flask was removed from the ice bath and heated to reflux for 1 hour while continuing to stir. The resulting top layer was transferred to a conical vial in which 1.5 mL (22.51 mmols) of 80 % sulfuric acid was added. 2.0 mL of water was added to allow a layer to form. The bottom layer was removed and transferred to another conical vial in which 2.0 mL of saturated sodium bicarbonate was added. The bottom, organic layer, was transferred to a conical vial. Calcium chloride, a drying agent, was used to collect the remaining aqueous layer that
instead of HCl, H2SO4 with a molar of 0.1 was used in its place. The
When studying DNA it is required to break apart the genome at certain places in order to study certain sequences and see how they properly function and or possibly find the source of a mutation (1). Separating the strands require a certain protein to ensure that the rest of the DNA strand remains intact (2). Restriction enzymes are vital to this process because they are able to scan the DNA molecule very slowly to find the certain recognition site required to complete an experiment, which usually runs from four to eight nucleotides(1). Once the enzymes find the sequence they are able to stop and to bind to the DNA wrapping around the strands that contain the desired nucleotides separating it from the other sequences, also known as cutting the sequence (3). That
In this experiment, we learned of effects and evidence of chemical change. We started the experiment with observance of a chemical reaction between the previously present 1.0 M of copper nitrate and the added 1.5 M of sodium hydroxide. When mixed with a stirring rod, this created a blue milky liquid known as sodium nitrate. The solution was then put into 50.0 ml of boiling water. This produced a reaction in the sodium nitrate, the reaction being a change from a blue milky liquid into a brown muddy liquid. The products of the chemical change being copper oxide and water. After a cooling process where there was no observed change, 1.5 M of hydrochloric acid was added to the present solution in the test tube. Once mixed with a clean stirring rod, the solution became transparent with the products of the change being copper chloride and
A multitude reactions occur in this portion of the lab. In the first section of the experiment, a small sample of sodium carbonate is placed in a test tube. Several drops of 6 M HCl are added. Observe what occurs and record the data, noting the odor and the color of the gas that forms. Repeat another reaction with sodium sulfite and record observations. Again, repeat with zinc sulfide. Starting a separate experiment, 6 M HCl is added to 1 mL of 0.1 M lead nitrate.
Alan Purves Hour 5 Javner Classifying Chemical Reactions Lab Summary Reaction #1 Type of reaction: Synthesis Balanced equation: 2Mg + O2 = 2MgO Observations: Once the magnesium was set on fire, it combined with oxygen and produced a very bright white light. The reaction left a white ashy powder on the tray.