Thermochemistry

• Endothermic Processes - Chemical and Physical Changes that occur with the absorption of energy
• Exothermic Processes - Changes that produce or release energy
• Thermodynamics - the study of the energy changes that accompany all processes, whether physical or chemical
• Thermochemistry - study of the energy changes that accompany chemical transformations in matter
• 1st Law of Thermodynamics - Energy cannot be created or destroyed, only transferred from one form to another
• Energy (E) - capacity to do work
• Heat flows from hotter to cooler objects until they reach thermal equilibrium (have equal T)
• Internal Energy - energy within the system because of nanoscale position or motion
• Enthalpy - is the total heat absorbed in a process at constant pressure if the only work done is pressure-volume work
• Hess's Law - states that if the equation for a reaction is the sum of the equations for two or more other reactions then Delta H for the 1st reaction must be the sum of the Delta H values of the other reactions