ELECTROCHEM

• Work


  Energy used to cause an object with mass to move against a force
• Heat


  Energy used to cause the temperature of an object to increase
• Forms of Energy


  • Kinetic Energy
  • Potential Energy
• Kinetic Energy


  The energy of a body by virtue of its motion
• Potential Energy


  The capacity of a body to do work due to its elevation above a reference point
• Joule


  The SI unit for energy
• 1 kg-m^2/s^2 = 1 joule (J)
• 1 cal = 4.184 J
• Thermodynamics


  The study of the relationship between heat, work, temperature, and energy
• Antoine Laurent de Lavoisier: '"Energy can neither be created nor destroyed. It can only be transformed from one form of energy to another."'
• Law of Conservation of Energy

  Energy can be transformed, but the total amount of energy in an isolated system remains constant
• System


  The portion we single out for study
• Surroundings


  Everything else
• Internal Energy, E


  The sum of all the kinetic and potential energies of the components of the system
• Endothermic Process


  A process in which the system absorbs heat
• Exothermic Process


  A process in which the system loses heat
• State Function


  A property of a system that is determined by specifying the system's condition, or state (in terms of temperature, pressure, and so forth)
• Enthalpy


  H = E + PV
• ΔH = q (at constant pressure)
• Thermochemical equation: 2H2(g) + O2(g) → 2H2O(l), ΔH = -483.6 kJ
• Thermochemical Equations and Enthalpy Diagrams

  • Enthalpy is an extensive property

  2. ΔH for a reaction is equal in magnitude, but opposite in sign, to ΔH for the reverse reaction

  3. ΔH for a reaction depends on the states of the reactants and products
• Calorimetry


  The measurement of heat flow
• Calorimeter


  A device used to measure heat flow
• Heat Capacity (C)


  The amount of heat required to raise the temperature of an object by 1 K (or 1°C)
• Molar Heat Capacity (Cm)


  The heat capacity of one mole of a substance
• Specific Heat Capacity (Cs)


  The heat capacity of one gram of a substance
• The specific heat of water is 4.184 J/g-K