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Lab 4: Stoichiometry

In: Science

Submitted By talothefox
Words 357
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Braidon Berry

Lab 4: Stoichiometry of a Precipitation Reaction

Background:

Stoichiometry is a challenging yet essential part of learning chemistry. By utilitizing the resources of this course, as well as the lab work. Learning this difficult section of the course can be done with hard work and sharp attention.

Purpose: The purpose of this lab was to learn how to connect calculations with real life examples. Doing this lab while doing the calculations for the molarity and molar masses, made it more challenging, however it did help in seating the knowledge and connecting it to the course.

Procedure:

To start, the dry Calcium Chloride Dihydrate, was weighed out and mixed with a small amount of distilled water. After that step the molarity of the CaCl2 was determined and logged in the data sheet.

Similar steps were followed in terms of measuring dry material, weighing it, and then mixing it with distilled water. This will be necessary in order to observe the reaction and calculate more.

Then the water was now filtered in the paper filter, this filter would later be dried in the sunlight and weighed to measure the mass of the product.

After the filtering was complete, the percent yield could be calculated, as well as the actual mass of the precipitate.

Data:

|Initial: CaCl2*2H20 (g) |1.0 g |
|Initial: CaCl2*2H20 (moles) |.0068 |
|Initial: CaCl2 (moles) |.0068 |
|Initial: NaCO3 (moles) |.0012 |
|Initial: Na2CO3 (g) |.12 |
|Theoretical: CaCO3 (g) |.68 |
|Mass of filter paper (g) |1 |
|Mass of filter paper +CaCO3 (g) |1.8 |
|Actual: CaCO3(g) |.82 |
|% Yield |101% |

Questions:

A) In my case, I achieved a percent yield of over 100%, this is most likely due to measurement errors on my part, as I don’t think it is supposed to be over 100.

B) It wouldn’t do very much, as CaCL2 was the limiting reagent.

C) It has 5.66 grams of pure CaCl2

D) It has 1.17 grams of pure MgSO4

E) You could run the experiment like normal, and compare the weights of the reactants before and after the experiment to get the weight you need.

Pictures;

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