Chemistry

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89 68th and Zinc A key aspect of chemistry once a reaction is completed, is analysis. So far you have quantitatively analyzed your white colored compound from the reactant side based on your knowledge of how much iodine and zinc reacted. Now you will determine the amount of zinc from the product side. To do this you will perform a titration which is basically a reaction between a known quantified substance, Na2H2EDTA, and an unquantified substance in this case, the amount of zinc ion in your product, zinc iodide. Once you have mastered the technique of titration, you will be given an unknown zinc salt and asked to find out how much zinc ion is in this substance. By doing this activity you will see how one quantity can be logically deduced

61 The Castle of Quantification A major development in the discovery of Nature's Chemical Laws was the use of the balance during experiments. By quantifying the mass of reactants and products, chemists uncovered regularities and created new generalizations about the physical world. These generalizations are important to us today. For instance, in industry the optimization of product is often extremely important economically. By knowing the relationship between reactants and products, chemists can predict how much product will be made from the amount of reactants they stafted out with; this minimizes the quantity of wasted reactants and thereby increases efficiency of the manufacturing process. Your job is to find this relationship. 1l l' ,.: ',:'- '1," ,,,,,,

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