Selena Tran
Chem 4A Lab Section 401
Formal Lab Report 1
09/21/2017
Gravimetric Analysis of Sulfate Formal Lab Report
Abstract:
Three measures of unknown sulfate salt was measured and placed into three beakers with water, Hydrochloric acid, and Barium Chloride. The solutions were heated until Barium Sulfate precipitated and the solutions were filtered through ashless filter papers to collect the precipitate. The filter papers were combusted until only the BaSO4 remained, and the precipitates were massed in crucibles. Using the masses of the BaSO4, the percent composition of the sulfate was calculated and used to determine the percent composition of the sulfate in the original unknown sulfate salt. The experiment performed was required for gravimetric analysis of sulfate to find the mass percent of sulfate in the original unknown sample. Without gravimetric analysis, it would be much more difficult to determine the mass composition of sulfate ions in the unknown sample. The ending result showed that the percent composition of sulfate in the unknown salt was approximately between 23.65% and 29.55%.
Introduction: It is important to be able to determine the amount of sulfate in unknown samples because sulfate is used in producing many varieties of things that humans are exposed to, including water and air. If humans ingest water where the concentration of sulfate is too high, it may cause diarrhea. High concentrations of sulfate can be used as laxatives as well. Sulfur
We then proceeded in testing for excess Ca2+ by adding two drops of .5 M K2C2O4 to test tube two and attentively observed to see if a precipitate formed, which it did. This meant that Ca2+ was in excess and C2O42- was the limiting reactant in the original salt mixture. We then cleaned up. Upon returning to our next class, we took the filter paper, with the precipitate on it, and took its mass.
The original 1.0 gram of the 50/50 mixture of the benzoic acid and benzil contain 0.5 gram of benzil. Thus, from 0.5 gram of benzil, only 0.266 gram of benzil was collected. The percent recovery of benzil was calculated to be 53.2%. This low percent recovery could be due to filtration errors. Some amount of benzil remained on the filtration paper that contained the MgSO4. In order for determining the purity of the
In experiment A the results from the precipitation of CaC2O4 H2O from the salt mixture were obtained by weighing the items listed on Table 1 on a scale.
In this task the concentration of an unknown sample of copper sulphate using colorimetry was used to find the concentration. In this investigation copper sulphate was used which is CuSO4.5H20 as a formula. To make a standard solution which was 1M, the same clean equipment was used to make up the standard solution as used to make sodium carbonate. However there was one difference and that was that the hot distilled water was used to dissolve the copper sulphate crystals. There had to be enough hot water in order to dissolve the crystals into the beaker and then add cold distilled water to cool the solution.
In reference to the analysis of anions, Table 1 shows that a precipitate was formed when our unknown was combined with HNO3 and AgNO3, thus indicating the presence of a chloride ion. Because our unknown did not form a precipitate due to HCl and BaCl2, separate, effervesce, or smell, we concluded that neither sulfate, nitrate, carbonate nor
The purpose of this experiment was to separate the component of three mixtures sand, sodium chloride and calcium carbonate then calculate the percentage by mass of each component recovered from the mixture. The other purpose of this experiment was to show us the students the concepts associated with physical and chemical properties of substances.
Sodium sulfate has a molar mass of 142.04 g/mol. It has a melting point of 884°C and can be an irritant.
To begin the procedure of the gravimetric analysis of chloride, 0.501g of Amine (C8H9NO) was weighed on an analytical balance and added to a 10mL volumetric flask. At this point 5mL of deionized water was added to dissolve the Amine. Then 5mL of 1 M AgNO3, which was already combined with 4 M HNO3, is added to the 10mL volumetric flask and stirred. To collect the AgCl precipitate,
Solutions of 6M H2SO4, 6M NH3, 6M HCl, 6M NaOH, and 1.0 M of NaCl, 1M Fe(NO3)3, 1M NiSO4, 1M AgNO3, 1M KSCN, 1M Ba(NO3)2, and 1M Cu(NO3)2 were given in separate test tubes. The color of possible precipitates, ions, acid-base behaviour, odor and solubility rules were conducted and were reported in Table 1. The key information about a mixture of two solutions was
b) Iron and Barium were present in unknown 3. Assigned unknown reacted with all 4 reactants and formed precipitate with 3 of them (Sodium carbonate, sodium hydroxide and Sulfuric acid). During the experiment it reacted very similarly to Iron (III) nitrate and Barium nitrate. For example, with it was tested against Ammonium Chloride, the color of the solution changed to a light green, very identically to Iron (III) nitrate and Ammonium Chloride. Besides, unknown 3 formed an orange brownish precipitate when it was tested with sodium carbonate. Iron (III) nitrate acted similarly. Moreover, unknown 3 reacted similar to Barium nitrate when it was tested against ammonium chloride and sulfuric acid. It did not form any precipitate with ammonium chloride but formed a very light white precipitate, which is identical to barium nitrate’s reaction against sulfuric acid. Therefore, the two present metal in unknown 3 are Iron and barium.
The goal of this experiment was to determine the empirical formula for a hydrate of magnesium sulfate and water. The technique that was used was measure the mass of the hydrate and then apply heat to evaporate the water. Then determine the mass of water that was in the hydrate and the mass of the remaining magnesium sulfate. The equation for the hydrate is determined by calculating the mole to mole ratio of the water and the anhydrous. The resulting formula will be formated as: MgSO4*_H2O
I came to the conclusion that they should appear (Cl, Br, I) from top to bottom respectively. Based on the previous information regarding mass increases as you go down the periodic table I was able to come to this conclusion. I observed that Cl had the least color concentration, then Br, then I had the most. The greater the color concentration, the greater the mass. This observed data let me come to my conclusion.
In this experiment, the Ksp for calcium sulfate dihydrate, CaSO4·2H2O, by titrating 4 times a calcium sulfate dihydrate solution with diprotic EDTA, H2(EDTA)2-. For each trial we found the Ksp by means of molarities and activities. The results for the Ksp using only molarities was very different than the Ksp using activities. The average Ksp using molarity only was 2.26 x 10-4 and the average Ksp using activity turned out to be 2.31 x 10-5. The actual Ksp however, is 3.14 x 10-5. A percent error of 26.6 % was calculated.
The cations in both the known and unknown samples were identified by using qualitative analysis, of which were determined to be acidic, basic, or neutral by using litmus paper. Acid-base reactions, oxidation-reduction reactions, and the formation of complex ions are often used in a systematic way for either separating ions or for determining the presence of specific ions. When white precipitate formed after adding hydroxide, aluminum ion was determined to be present in the solution. However, nickel was determined to test positive when the solution changed to a hot pink color after adding a few drops of dimethylglyoxime reagent and iron was present when the solution was a reddish brown color when sodium hydroxide was added to the mixture at the very beginning of the experiment. Qualitative analysis determines that ions will undergo specific chemical reactions with certain reagents to yield observable products to detect the presence of specific ions in an aqueous solution where precipitation reactions play a major role. The qualitative analysis of ions in a mixture must add reagents that exploit the more general properties of ions to separate major groups of ions, separate major groups into subgroups with reactions that will distinguish less general properties, and add reagents that will specifically confirm the presence of individual
The total sulfur content (TS) was measured for some outcrop and well samples. The TSvalues, which represents pyritic sulfur, are generally low in the