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Determination of a Chemical Formula

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Determination of a Chemical Formula
10/19/2011
Akruti Patel
Lab Report #4: Determination of a chemical formula: the empirical formula of Magnesium Oxide 1. Purpose: Determine the empirical formula of magnesium oxide from the percent composition (this can found using the Analytical Method and the Synthesis Method). 2. Introduction: In the late eighteenth century, combustion has been studied extensively. In fact, according to Steven and Susan Zumdahl, Antoine Lavoisier, a French Chemist, performed thousands of combustion experiments and measured masses of every single reactant and product, including those which were gases (for example, Carbon Dioxide, Nitrogen, Hydrogen, and Oxygen). Lavoisier considered measurements to be an essential tool for chemistry. He observed that as the physical and chemical properties of the products and the reactants differed, the total mass of the products was always the same as the total mass of the reactants. His experiments suggested that “in a chemical reaction, mass is neither created nor destroyed” as summarized in the law of conservation of mass. (Zumdahl and Zumdahl 41) This experiment demonstrates the law of conservation of mass by and how it can be used to determine the empirical formula of magnesium oxide (MgO). The empirical formula is the simplest number ratio of each element in a substance. In order to get the empirical formula, the magnesium must react with the oxygen to get magnesium oxide. The goal of this experiment is to measure the mass of the magnesium, chemically change it to magnesium oxide, and then find the measurement of the magnesium oxide. 3. Methods: Obtain a clean, dry crucible and a wire triangle. Heat the crucible for approximately five minutes over a Bunsen burner. Make sure to heat the crucible to the hottest part of the Bunsen burner flame (above the tip of the inner blue cone of the flame) to ensure that it glows dull red. After five minutes, turn of the burner. Allow the crucible to cool until there is no heat radiating



Cited: Zumdahl, Steven, and Susan Zumdahl. "Atoms, Molecules and Ions." Chemistry. 8th ed. Belmont, CA: Brooks Cole, 2008. 41-42. Print. CHEMISTRY. (1)

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