Unit 6 - Chemical Reactions

Writing and Balancing Chemical Equations

• Chemical Equations - A chemical formula representing the reactants and products of a chemical reaction

  • Is composed of reactants and products

• Symbols in Chemical Equations

  • (s), (l), (gas) indicates state of matter

  • (aq) indicates aqueous

  • < - - > indicates the reaction is reversible

  • Various symbols above the reaction indicate that it is heated, the temperature and pressure of the reaction, and what catalyst is used in the reaction

Percent Composition and Molecular Formulas

• Mole Ratios - The ratio of the subscripts in the molecule

• Empirical Formula - The chemical formula that displays the simplest whole number ratio of the atoms in the molecule

• Molecular Formula - The chemical formula that displays the actual ratio of atoms in the molecule

  • Aka “true ratio“

• Percent Composition - The percent of the total mass each element in a compound takes up

Types of Reactions

• Synthesis - 2+ reactants combining to form a product

• Decomposition - A reactant breaks down into 2+ products

• Combustion - A substance reacting with oxygen

• Single Replacement - One ion displaces another to form a compound

• Double Replacement - Two ionic compounds exchange ions to form a new compound

• Solubility Rules - https://emissary.edgenuity.com/https://media.edgenuity.com/contentengine/Common//pdfs/3210/Solubility%20Rules.pdfhttps://emissary.edgenuity.com/https://media.edgenuity.com/contentengine/Common//pdfs/3210/Solubility%20Rules.pdf

• Activity Series - Description of the relative activity of elements

Oxidation Reduction

• Oxidation - Loss of electrons

• Reduction - Gain electrons

• Oxidation-Reduction Reaction - Reactions where electrons are transferred from one substance to another

  • Aka redux reactions

  • The oxidized substance is called the reducing agent

  • The reduced substance is called the oxidizing agent