The goal of these experiments within this lab was to determine the formula and composition of the colored cobalt compound. The beginning experiment was a synthesis. The cobalt compound was synthesized, air dried, then put away for future use throughout the lab. Using the synthesized cobalt compound, % halide, % NH3, and % Co was found. % halide was found using a silver nitrate solution combined with the synthesized cobalt compound. The solution filtered in the crucibles is then dried in the oven until a constant weight was found. % NH3 was found by gathering ammonia from cobalt compound solution into a boric acid solution. The boric acid ammonia solution is then titrated using standardized HCl. % CO was found using spectroscopy. The cobalt compound falls under the category of chemistry called coordination chemistry, which is the interaction between ligands and metals. Ligands bond to the center metal atoms to form a complex. Alfred Werner is considered the father of coordination chemistry. Coordination compounds are the products of reactions when anions bond to a metal ion. Lewis acids are substances that can accept nonbonding electrons, and lewis bases are substances that can give nonbonding electrons. The bonds …show more content…
My compound should have been a darker shade of orange but it was still orange. More than likely it was human error that affected my percent yield. I might have left some of the solids behind in the flask after transferring the compound somewhere else. Or even the equipment could have caused the error. There is the possibility that the measurements of some instruments were incorrect. Many different factors could have contributed to the percent yield being that far off. Overall my results were reliable but I believe they could be more accurate and reliable. Some percent values were more reliable than others. Errors occurred throughout the entire experiment because it is impossible to do an experiment and have 0
The experiment was not a success, there was percent yield of 1,423%. With a percent yield that is relatively high at 1,423% did not conclude a successful experiment, because impurities added to the mass of the actual product. There were many errors in this lab due to the product being transferred on numerous occasions as well, as spillage and splattering of the solution. Overall, learning how to take one product and chemically create something else as well as how working with others effectively turned out to be a
The purpose of the Unknown White Compound Lab was to identify the unknown compound by performing several experiments. Conducting a solubility test, flame test, pH paper test, ion test, pH probe test, conductivity probe test, and synthesizing the compound will accurately identified the unknown compound. In order to narrow down the possible compounds, the solubility test was used to determine that the compound was soluble in water. Next, the flame test was used to compare the unknown compound to other known compounds such as potassium chloride, sodium chloride, and calcium carbonate. The flame test concluded that the cation in the unknown compound was potassium. Following, pH paper was used to determine the compound to be neutral and slightly
The purpose of conducting experiment was to determine the identity of white compound. Based on the 5 gram of unknown white compound several experiment conducted including solubility test, pH test, flame test, and ion test. Several materials including chemicals used throughout experiment and will be described through paragraphs.
I would suggest to students performing the nitration to make sure their benzoic acid product is very fine and broken up before reacting it, as it has a tendency to clump together when it dries and thus proves very difficult to react in solution. I would also suggest keeping a very close eye on the temperature when adding the sulfuric/nitric acid mixture dropwise, as the reaction has a tendency to spike in temperature
In this experiment, there were several objectives. First, this lab was designed to determine the difference, if any, between the densities of Coke and Diet Coke. It was designed to evaluate the accuracy and precision of several lab equipment measurements. This lab was also designed to be an introduction to the LabQuest Data and the Logger Pro data analysis database. Random, systematic, and gross errors are errors made during experiments that can have significant effects to the results. Random errors do not really have a specific cause, but still causes a few of the measurements to either be a little high or a little low. Systematic errors occur when there are limitations or mistakes on lab equipment or lab procedures. These kinds of errors cause measurements to be either be always high or always low. The last kind of error is gross errors. Gross errors occur when machines or equipment fail completely. However, gross errors usually occur due to a personal mistake. For this experiment, the number of significant figures is very important and depends on the equipment being used. When using the volumetric pipette and burette, the measurements are rounded to the hundredth place while in a graduated cylinder, it is rounded to the tenth place.
Put 1mL of 0.1M cobalt (II) chloride hexahydrate dissolved in 95% ethanol into a test tube. Then add 1mL of deionized water. Tap the end of the test tube to mix the solution and record the pertinent data in section 2 of the Data Table. Discard the solution in the appropriate container as directed to you by your lab instructor.
The question that was proposed for investigation was: Can the theoretical, actual, and percent yields be determined accurately (Lab Guide pg. 83)?
This experiment synthesized luminol (5-Amino-2,3-dihydro-1,4-phthalazinedione) and used the product to observe how chemiluminescence would work. The starting material was 5-nitro-2,3-dihydrophthalazine-1,4-dione, which was, after addition of reaction agents, refluxed and vacuum filtered to retrieve luminol. Using two stock solutions, we missed our precipitated luminol with sodium hydroxide, potassium ferricyanide, and hydrogen peroxide, in their respective solutions, in a dark room, to observe the blue light
One possible source of experimental error could be not having a solid measurement of magnesium hydroxide nor citric acid. This is because we were told to measure out between 5.6g-5.8g for magnesium hydroxide and 14g-21g for citric acid. If accuracy measures how closely a measured value is to the accepted value and or true value, then accuracy may not have been an aspect that was achieved in this lab. Therefore, not having a solid precise measurement and accurate measurement was another source of experimental error.
The metal Ni2+ and the ligand ethylenediamine (en) are studied in this experiment. Solutions are prepared with varying compositions of Ni(en)n2+. Using the equilibrium constants, it is possible to identify which species is present. If the constant for the formation of a species where n is 2 is larger than a species whose constant equals 3 then the former species is pre-dominant. Jobfs Method is limited in that it will give non-integral values of the n present if a fourth complex, ZLn+1, exists. If there is a large variation between the equilibrium constants then only two complexes will be present in the prepared solutions. The absorbance values are plotted, then the value of n can be calculated.
In our experiment we utilized the hydrate cobaltous chloride. Hydrates are crystalline compounds in which one or more molecules of water are combined with each unit of a salt. Cobalt (II) chloride hexahydrate is an inorganic compound which is a deep rose color in its hydrated form. As an inducer of
Evaluation I believe that some of my results were inaccurate because there was a misread with the temperatures or that we didn’t let the thermometer reach its final settling temperature and recorded the temperature too early. Also we might have started the reaction too early before the solution was at the correct temperature because the thermometer was in the beaker rather than the test tube and not measuring the
Overall I think I carried out the experiment in a precise way and I took my time trying to make all my measurements as accurate as possible so that my data is reliable. Next time I will do more tests instead of just 3 so I have more results and so I could get a more accurate average. I will also do the experiment with more fruit juices to see if there are other fruits with a higher content of vitamin C. I will do an experiment to see if there is a difference in Vitamin C levels between fresh juice and store bought juice. I can also test different brands of juice to see if they have different levels of vitamin C.
At this point, the error is 30%! Any reading less than 10% of full scale should be viewed with suspicion since most meters are very inaccurate in this range. Circuit Diagrams For this experiment we used a power supply source, voltmeter/ammeter/ohmmeter. Fig.
Chemwiki UCDAVIS (n.d) claims that the colour a coordination compound has can be determined by using the Crystal field theory. These colours are then used for the creation of pigments that are used for dyes in the industry of textiles. Coordination compounds are able to form these colours because their absorption energy falls within the range of the visible light spectrum. The colour that is visible in all chemical compounds is an indicator of the physical properties of the substance at atomic level.