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