We then slowly added 25ml of chilled deionised water to the filtrate to initiate crystallization by using a measuring cylinder and a dropping pipette, once we had done this we left it for about 10 minutes to allow crystallization at room temperature. We then weighed a filter paper which we will use later in the experiment. We then collected the crystallized acetylsalicylic acid by vacuum filtration in a Buchner funnel and washed the product with a little ice-cold water. We then pre-weighed a clean, empty watch glass and labelled it with our initials and the date, we did this do we could easily identify that it was ours when we go to weigh it with the crystals on. We
Universal indicator being green shows that the water is neutral 3. Sodium darting on water shows the reaction was vigorous in nature and this was also due to the fact that the hydrogen was propelling the piece in the water 4. The sodium piece becoming spherical shows that the reaction was exothermic. The heat produced melted the sodium piece and made it spherical as the melting point for sodium is low and the heat produced is sufficient to melt it . 5.
Lastly, it told us to repeat the same steps until we had three calcium chloride scoops in the beaker and repeat for two more trials for accurate results. To sum up the experiment, it said to record the average change in temperatures to the class averages to graph a bar graph comparing both of the averages. That’s the procedure on how to conduct the experiment correctly. The averages that my group received for zero scoops were 0.5 degrees Celsius, one scoop was 6.5 degrees
Numerous tests have been created to measure the magnitude of said concentrations. The tests range from simply evaporating the solvent and examining the leftover nonvolatile residue that remains, which is known as the total dissolved solids (TDS) of the sample, to chemical titrations using indicators (EDTA), to advanced spectroscopy of the sample using emission spectrums to determine ion absorbance values (AA Spectroscopy). There are a few differences between AA Spectroscopy and EDTA titrations when it comes to determining water hardness as both tests use different techniques. AA Spectroscopy is used to determine the concentration of metal ions in a water sample. A spectrophotometer is used to read the absorbance value of the cations in a flame that emits a photon read by the machine.
Then, reweigh the cylinder to the nearest milligram. Calculate the density of the water then compare the measured density of the water with the value from the handbook for the temperature of this lab experiment. Now grab an unknown liquid and record the ID number and determine and verify the density of the unknown liquid. The same method is to be used as described for water. III.
The ester studied was “3,” the acid used was 9.5 mL of “B,” and the alcohol used was 18.1 mL of “C.” A few substances were added to augment the production of the ester. Sulfuric acid (H2SO4) was added using a dropper bottle to catalyze the reaction. The desiccant in this reaction was drierite and was used to absorb the water byproduct. This prevented the ester from breaking apart into its constituents. The cold finger condenser was used to trap evaporated gas from the heated mixture, and condense it back into
In the lab, “Properties of Hydrates,” the purpose was to compare the properties of several well observable hydrates and to determine if dehydration is a reversible or irreversible change. The lab consisted of attaining a pea-size sample of each compound, burning it over a bunsen burner, and comparing the starting mass and the mass lost after the combustion. These results are important to be able to identify a variety of different chemicals that contain water molecules as part of their crystalline structure. Some can be removed by heating (resulting in evaporation) and some remain mostly unchanged. In this lab the answer will be found.
Abstract This experiment was carried out to determine the species of the unknown organism. Once a choice of the unknown was made a Gram stain was conducted to determine the gram nature and morphology of the organism which was Gram negative bacilli. Based on those results a citrate utilization test was performed resulting in a positive test. Following the flow chart the next test to conduct was a motility test which also had a positive outcome. Lastly, a glucose fermentation test was conducted to determine the unknown organism.
Then 35 ml of 1.00 M of Sodium hydroxide was measured and set aside. Using the calorimeter, the hydrochloric acid was stirred heartily and its temperature was recorded as the initial temperature. The temperature of the Sodium hydroxide was assumed to be similar because they were both in the same conditions (lab) for the exact amount of time. Next the Sodium Hydroxide solution was added to the hydrochloric acid solution in the cups and stirred until the temperature stabilized. This was recorded as the final
On the second day of incubation, the plate was removed from the incubator and placed over a hot plate heating Iodine solids. The smoke of the Iodine stained the plate to display the presence or absence of a halo around the bacteria 2.12 Lipid Hydrolysis This test was done by making a single line streak inoculation on a tributyrin agar plate and allowing incubation. After the incubation period, the plate was observed for the presence or absence of a halo around the bacteria. 2.13 Gelatin Liquefaction A gelatin deep was deep stabbed and incubated. After incubation the tubes were placed in 4ºC for 30 minutes.
This test was conducted for the purpose of selective and differential whether or not my organism can tolerate high salt concentrations. It is based on the mannitol fermentation. The phenol-red indicator helps to identify the bacteria. Upon viewing my results it was determined that my colonies did not ferment mannitol. This was easily observed because they remained translucent.
All things considered, the results proved that the unknown substance or element was barium since the calculated density was 3.9 g/mL. To expand upon, the density was calculated by measuring the mass of the metal and using the displacement method to determine the volume of the metal. Also, the best method of disposing the storm water would be to contact a Wastewater Treatment Plant (WWTP) so that they could put it through a purification process, making all that water reusable. Meanwhile, the percent of recovery was calculated by the formula Percent Recovery=observed valuetrue value *100%. Furthermore, according to the pie chart created in the data analysis, the sample given contained of the percent by mass for metal to be 5.2%, salt was 3.3%, wood was 3.1%, plastic was 4.5%, rock was 12.5%, sand was 11.8%, and water was 59.6%.
What happens during this stage of the experiment showing visual change and acidic reaction that is becoming weaker as the molecules are deprotonated to become equal parts within the solution. So by finding the molar ratios we learned that acid to base are 1:1 when equally balance or concentrated. So therefore concentrations at stoichiometric end point can be found by plugging in the values to formulate a dilution equation as seen above. When expressing calculations I found when doing the Titration of an Unknown Acid I discovered that with .1 mL of Sodium Hydroxide and at least 10 mL Anthocyanin as/or acetic solution will produce an average molarity of 0.9 or higher according to my
The ultimate objective of this report is to narrow down the possibilities of bacteria using a series of test, while eliminating unlikely choices. Using the skills in the microbiology lab you can discover and make a educated decision of determining the mystery microbe, with the enough supported information collected from the chemical test and stains. There will be 17 test that will be run, each of this test will bring an important clue in determining the Mystery Microbe based on their environmental
It is necessary to understand what each test reveals about the unknown. Citrate tests are performed in order to distinguish between different enteric bacteria by seeing which can use citrate as the sole carbon source. MR/VP are tests that are used to distinguish between different types of fermentation either mixed acid or butanediol and test for the production of acetoin. H2S production is used to determine whether or not the bacteria can produce hydrogen sulfide. Mannitol high salt testing is done in order to determine if the bacteria is salt tolerant and can ferment mannitol.