Two Outliers Lab Report

Methanol, ethanol, 1-propanol, and 1-butanol are alcohols that contain both London-dispersion forces and hydrogen bonds. Hydrogen

If the temperature in the apparatus increases too quickly, it’s difficult to record to exact temperature at which the first drop of liquid falls and then again when the mixture is completely liquid. This would result in the wrong melting point range being recorded. Additionally, experiment three heavily relied on the results from experiment two. Failing to extract all the aspirin from the organic solution in experiment two would result in more impurities in the unknown component. Thus, lowering and broadening the melting point

alcohol, making it either primary (1° ), secondary (2° ), or tertiary (3° ). If the OH is bonded to only one other carbon, it is a primary alcohol (eg. 1-butanol); if bonded to two other carbons, it is a secondary alcohol (eg. 2-butanol); if bonded to three other carbons, it is a tertiary alcohol (eg. 2-methyl-2-propanol). Due to the placement of the hydroxyl functional group in each of the degrees of alcohol, the reactivity of each should be impacted. This means that all three

1-Pentanol has a boiling point of about 138C which is much greater than the Pentanal with 102C which caused by having OH polar group and it also allows 1-Pentanol to form hydrogen bonds with water, therefore increasing its intermolecular forces and eventually creating a high boiling point.

    One possible source of error that can affect the results was that a mercury thermometer was used instead of an electronic one. The use of a mercury

My unknown organism #6 is Morganella morganii, which is a gram-negative bacillus rods commonly found in the environment and also in the intestinal tracts of humans, mammals, and reptiles as a normal flora. (3, 5) This bacterium Morganella morganii, was first discovered in the 1906 by a British bacteriologist named H. de R. Morgan. (2) Despite its wide distribution, it is an uncommon cause of community-acquired infection and is most often encountered inpostoperative and other nosocomial settings. (2, 3) Morganella morganii infections respond well to appropriate antibiotic therapy; however, its

B. Claim: As we go from methanol  ethanol  1-propanol  1-butanol the dispersion forces increase.

Again with the same temperatures of one degree, eleven degrees, twenty degrees, thirty degrees, and forty degrees. All the temperatures are in Celsius. The one degree C time is at 24.59 seconds, only two seconds off from the first trial. The eleven degrees C time has 20.39 seconds. At twenty degrees C, the data showed the time was 15.54 seconds. Thirty degrees C had the lowest time of the thirty degrees group, at 8.97. The last temperature was forty degrees C with the lowest time at 7.28 (See appendix two). All the data for trial two supports the hypothesis for this

An unknown was given to our group from the professor. The unknown was in nutrient broth, the group received unknown number 3. And the task was to identify the unknown and try to make an educated guess, and identify the unknown #3.

Some possible errors would include inconsistent temperatures that varied by about five degrees, because of opening the hot bath a lot of heat was lost, as well as, waiting till the end of lab to run the cold trials so the ice was melted caused a increase of temperature. Human error was another aspect that affected the data. Since the disk assay was based on observation of when the disk floated that data probably was not accurate to the exact second to when the disk reached the top of the solution. Another possible error is that the hydrogen peroxide was left out during the experiment for example the cold solution was left out the majority of the period. Since hydrogen peroxide decomposes more in light, this could have played a small role of increasing the reaction

This is important because the temperatures need to be constant in order to have valid data. If a certain temperature was set, then variables such as air conditioning would not affect the test tubes environment. A second way to improve the validity of this experiment is to conduct more trials. In this experiment, there were only 3 trials conducted for the whole class. If more trials were tested, the class average would be more specific.

I can narrow down my unknown substance to either Ethanol or 2-proponal. Ethanol’s density is only 0.001g/mL higher than my own measurements, but its boiling point is 8.4̊C lower than GNR’s. Whereas 2-proponal’s density is off by 0.003g/mL and its boiling point is only off by 4.5̊C. If I were to make an educated guess I would lean more towards Ethanol. Both the precision and accuracy of my data was far greater in density than in boiling point and Ethanol’s density is closer to GNR’s than any other substance.

Even though the result of an experiment is accurate and matches the literature value, it does not mean that there were no mistakes made. As the difference of the percentage uncertainty and the percentage error suggests there were random errors made. First of them was the heat energy lost to the surrounding environment during the experiment process taking place. This caused the recorded highest temperature to be smaller than the actual highest temperature that was meant to reach. This could have been prevented by adding in more and perfect

The results from the NMR of 1-propanol showed 3 different prominent peaks with the peak at 2.2 cm-1 being the acetone. Because 1-bromopropane has three non-equivalent hydrogens it was found to represent this set of NMR data. The other product, 2-bromopropane only had 2 different types of hydrogens and would have only had 2 peaks. Further analysis of the structure of 1-bromopropane showed that the hydrogens closest the bromine group were an indication of peak A in the graph. Because of the electronegativity of the bromine, this peak was located further downfield. There were 2 neighboring hydrogens so using the n+1 rule gave the 3 peaks. Going down peak B showed the next carbon which had 5 neighboring hydrogens thus giving 6 peaks. Finally, the carbon furthest away from the bromine was found at peak C. It had 2 neighboring hydrogens and provided 3 peaks.

The results that were revealed were thought to be accurate and reliable as many factors were controlled to enable the best quality. The results that a constant rise in the combustion occurred as each alcohol’s carbon chain increased with one exception indicates that the reliability of this experiment has to be examined. With such a high percentage error from these results means they cant be definitive. Also only three trials were conducted on the five different alcohols. If the experiment were to be conducted again I would conduct five trials on each alcohol to get a better average.