Final Draft | Kabir Nadkarni - artsocial.info
Calculating the mass of calcium chloride needed for a mL M calcium . calcium CaCl2: Balanced chemical equation: CaCl2 (aq) + Na2CO3 (aq) CaCO3 However, in the experiment conducted, the experimental ratio of CaCl2 to Calculating the theoretical yield of the precipitate (CaCO3): In the reaction that. Formal Lab Report Requirements Your lab report should be setup exactly as seen on Y. Name 1 Honors Chemistry Mrs. Klingaman – Mods North Hunterdon High was to produce and separate calcium carbonate through a precipitation reaction. This precipitate was then be mass and percent yield was determined 2). sodium carbonate and calcium chloride react as follows: Na2CO3(aq) + specific mole (mol) ratios, in this case a ratio. In this experiment, you will use stoichiometry to determine which reagent ml. Mass of. Mass of. Mass of. Na2CO3. CaCl2 filter watch. CaCO3 paper (g) On the data table, answers assume perfect.
Ex Upon the completion of three trials, the percent yield of calcium carbonate produced was What are the larger implications of your findings as they relate to your purpose?
Ex The results of this experiment suggest that filtration is a fairly successful way to separate a precipitate from solution.
Furthermore, it is necessary to calculate the theoretical yield of a product based on the stoichiometric quantity of the limiting reactant. This way, the actual yield products can be directly compared for the determination of percent yield.
The background is between full paragraphs depending on the detail of underlying principles used. Briefly develop the underlying principles or theory which is crucial to this experiment.
Percentage Yield Lab Answers - SchoolWorkHelper
Any important equations or reactions utilized in this experiment should be included, labeled, and briefly explained in this section of the report. It may also explain how an out-of-the-norm instrument works like how a spectrophotometer reads wavelengths of light to differentiate molarities based on absorbance. Also, the portions that you paraphrased or quoted must be highlighted or underlined. Ex In this experiment, a double replacement reaction between calcium nitrate [Ca NO3 2] and sodium carbonate [Na2CO3] was performed, resulting in the formation of the solid precipitate, calcium carbonate [CaCO3] according to equation 1 below: The term insoluble means that a substance cannot be dissolved in the given solvent, most typically water.
In the case of this particular experiment, the precipitate was separated from an aqueous solution of sodium nitrate [NaNO3] which was also produced as a byproduct of the reaction. Filtration can either be based on differences in particle size or state of matter; here, the difference in states of matter between the two products of Reaction 1 allows the separation of solution and precipitate.
Upon massing the precipitate, the percent yield can be determined according to equation 1 below: Actual yield Theoretical yield x Equation 1 The actual yield is the measured mass of the precipitate produced in the experiment. The theoretical yield is the maximum calculated mass of the precipitate that could be produced given the origin starting quantities of each reactant. In order to determine this theoretical mass, the limiting reactant must be determined and the stoichiometric molar ratio using Reaction 1 between the limiting reactant and precipitate must be applied to the calculation.
List all equipment, chemicals, or other materials used in bullet form. If chemicals are used, they should be listed by the chemical formula, name. If approximate masses used are known they should be included. Solutions used with known molarities should always be included. Briefly describe, in a short paragraph, how the experiment was performed and what MAJOR equipment was used.
You are giving an overview of what occurred so that another trained scientist could repeat your experiment with the same basic principles in mind. Ex Solutions of 1.
Equal volumes of each reactant were combined in an open test tube and stirred to ensure thorough mixing. A solid white precipitate of calcium carbonate and an aqueous solution of sodium nitrate were created as described by Reaction 1.
A basic gravity filtration system was setup using a funnel and ring stand. The contents of the test tube were then filtered and rinsed with deionized water in order to ensure separation of the precipitate from the aqueous solution.
Upon drying, the mass of the precipitate was measured. Two more trials of the experiment were then preformed. All data and measurements taken in the lab should be arranged into a data table and placed into this section of the report.
Often, you can set it up to match the data table given in your lab experiment. Make sure that every table has a title and that every portion of the table is labeled with the measurement and units. Whenever possible, make sure that the data table does not end up split between two pages even if this means that the data section must start on a separate page Y.
Name 4 Ex Data and Measurements Table: This table puts all the important calculations in one concise location and it should be very organized. Whenever possible, make sure that the table does not end up split between two pages even if this means that the results section must start on a separate page.
- Post Lab Questions
- CHEM 2 LAB REPORTS
The results section should NOT include an ounce of calculations within it, only final result values. This section will NEATLY demonstrate the calculation work and set-ups including all the data numbers used and appropriate units. You may type the calculations directly into the lab report, or, if you choose, calculations may instead be hand written but they must be neatly written in INK, not pencil! Show ONE sample calculation for each type of calculation that is necessary.
For example, you would show work for how each calculation was performed, but for ONE trial only the assumption is that you did the calculations for all trials exactly the same so one sample is enough to determine if it was calculated correctly or not.Chem 60 Experiment 9: Stoichiometry
Typically, the trial with the best results is the one chosen for showing sample work. Be sure to include a title addressing which trial is detailed in the sample calculations.
If the post-lab requires any graphs they may be inserted directly into this section or, if hand drawn in ink they are to be attached directly before the conclusion section of the lab report. Trial 3 1 Actual Mass of Precipitate: Actual yield of calcium Graph 2: Percent yield of calcium carbonate in each of the three trials carbonate in each of the three trials 1.
This is because the two prepared solutions were both clear and transparent. Had there been visible solutes in either solution, the presence of that visible solute in the mixed solution could have signified that it was in excess.
However, since no visible solutes were seen in the mixed solution, this is not a valid conclusion. However, after applying stoichiometry, it can be concluded that the limiting reactant was indeed calcium chloride.
Percentage Yield Lab Answers
The balanced chemical equation of the chemical reaction is as such: According to this balanced chemical equation representing the double displacement reaction that occurs, the ideal stoichiometric ratio of reactants CaCl2 and Na2CO3 is 1 mole CaCl2 to 1 mole Na2CO3.
Another conclusion after applying stoichiometry is that the theoretical yield of CaCO3 the precipitate should have been 1. Hence, the theoretical yield mass of product predicted by stoichiometry in perfect experimental conditions of CaCO3 is directly proportional to the amount of CaCl2 available in the reaction, the molar ratio between CaCl2 and CaCO3 presented in the balanced chemical equation 1 mole CaCl2 aq to 1 mole CaCO3 sas well as the molar mass of CaCO3 The percent yield of each trial was found by expressing the actual yield as a percentage of the theoretical yield, and then the percent yields of the three trials were averaged.
This is supported by the quantitative observations, seeing as the actual yield of the precipitate in Trial 3 1. Also, the filtered solution of Trial 3 was a lot milkier than the others, signifying that some of the precipitate might have bypassed the filtration process.
When I noticed the problem during the experiment, I proceeded to slow down the filtration process and allow each phase of solution to filter for a longer period time, so that it did not accumulate to above the height of the ridge in the filter paper. However, this was only realized after beginning the Trial 3 filtration process, and so some precipitate might have leaked in the beginning.
Post Lab Questions
A possible solution for such a condition could have been to use larger filter papers if available, seeing as even if an erroneous fold did occur in the paper, it would not allow solution to go through without filtration. Also in Trial 3, a qualitative observation was that I noticed an unwanted speck of dust on the filter paper after I took it out of the overnight drying location.
At this point I could not extract it from the dry precipitate sample, because that would risk extracting some of the precipitate as well and would cause an even larger random error in the mass readings. Therefore, I had no choice but to leave it as it was, and include it in my mass reading.
Therefore, it can be speculated that the actual yield of Trial 3 might have really been even smaller than 1. A possible solution for such random errors would be maintaining a cleaner environment for chemical storage, especially when materials need to be stored for long periods of time such as over a few nights for drying.
Another experimental flaw is that it could not be confirmed that all the aqueous NaCl had been rinsed from the filter paper and separated from the precipitate. Distilled water was used to run any extra NaCl that might have been caught in the filter; however, a better process of separation might have helped. This is especially significant considering much of the precipitate had covered the filter paper before the NaCl ions were poured, and so they might have been stuck and unable to pass through the layer of precipitate.
Yet another visible systematic error was that after pouring the distilled mixed solution out of the beaker, a lot of the precipitate still remained stuck to the bottom of the beaker. Even after using distilled water to ease drainage, it did not budge.
Hence, since all the precipitate formed was not accounted for in the following mass measurements and calculations, this may have been a leading cause of the percent yields Hence, the systematic error caused mass readings to be consistently lower than they should have been. A viable solution would have been scraping the remaining precipitate off of the bottom of the beaker with the help of a stirring rod.