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Chemistry 11.1. “Describing Chemical Changes”. Review. A. Reactants Products B. Dalton’s Theory… “As reactants are converted to products, the bonds holding the atoms together are broken and new bonds are formed.” C. Law of Conservation of Mass…
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Chemistry 11.1 “Describing Chemical Changes”
Review A. Reactants Products B. Dalton’s Theory… “As reactants are converted to products, the bonds holding the atoms together are broken and new bonds are formed.” C. Law of Conservation of Mass… “Mass is neither created nor destroyed.”
II. Equations A. Word Equations 1. Def – words used to describe a chemical reaction. -no #’s are involved 2. Ex: Iron + Oxygen Iron (III) Oxide 3. Ex: Hydrogen Peroxide Water + Oxygen 4. Ex: Methane + Oxygen Carbon Dioxide + water
5. What is the word equation for…Pure copper can be produced by heating copper (II) sulfide in the presence of diatomic oxygen from the air. Sulfur dioxide gas is also a product in this reaction. Copper II Sulfide + Oxygen Copper + Sulfur Dioxide
B. Chemical Equations 1. Def – Using chemical symbols to write a chemical formula. - #’s are involved 2. Ex: Fe + O2 Fe2O3 -this is a skeleton equation b/c it is not balanced
C. Balanced Chemical Equations 1. Follows the Law of Conservation of Mass. 2. 4 Fe + 3 O22 Fe2O3