Stoichiometry

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Stoichiometry
Rebekah Muller
Chemistry Lab 101-02
Instructor: Sam Stevenson

Abstract: Stoichiometry is used to figure out how much potassium chlorate in a mixture of potassium chlorate and an inert substance (a substance that does not react chemically). By determining the mass of the product experimentally, the mass percent composition is calculated stoichometrically. After finding the mass percent composition, the final calculation to find is percent error (with the accepted value given). In this experiment, we use a solid that contains potassium chlorate as the reactant and then determine how much potassium chlorate was actually in the solid. To determine the amount of potassium chlorate, we heat up the solid on a Bunsen burner and measure how the solid as changed while the reaction was taking place.
Objective:
There are four objectives to this lab: to calculate the theoretical and percent yields, predict the effect of experimental error on percent yield, calculate the percent composition, and calculate the percent error.
Introduction:
The purpose of this lab is to determine the mass percent composition of potassium chlorate in an unknown substance by using Stoichiometry. Stoichiometry is the calculation of the quantities of chemical elements or compounds involved in chemical reactions. In this lab, the decomposition of the reaction would further the calculations of potassium chlorate in the mixture. Decomposition means the breaking down of compounds or mixtures into the form of elements or smaller substances. The hypothesis trying to be proven is that it is possible is find the mass of a compound can be determined through Stoichiometry and experimentally. Experimentally, the mixture will be heated. If the heating continues for an extended amount of time, the reaction will not be affected because the reaction has already been…...

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