Thermodynamics

• Enthalpy is a measurement of the difference in energetic states before and after a reaction has occurred
• What are the three types of motion?

  1. Rotational
  2. Vibrational
  3. Translational
• The 2nd law of thermodynamics states that the entropy of the universe increases for any spontaneous reaction
• The 3rd law of thermodynamics states that the entropy of a pure perfect crystalline solid at 0 Kelvin is zero
• Name the state functions

  1. Enthalpy
  2. Gibbs energy
• For an endothermic reaction to be spontaneous at standard state conditions the reaction must have a positive entropy
• For a reaction to always be spontaneous under standard state conditions, ∆H must be negative and ∆S must be positive
• For a spontaneous process

  $∆S(universe)>0$
• The universe is composed of system and the surroundings+

  $∆S(universe)=$$∆S(system)+$$∆S(surroundings)$
• Reversible process equation

  $∆S(univ)=$$∆S(sys)+$$∆S(surr)=$$0$
• Irreversible process equation+

  $∆S(univ)=$$∆S(sys)+$$∆S(surr)>0$