pk 2 chem 6 - Chapter 17 Free Energy and Thermodynmics...

Info iconThis preview shows pages 1–9. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 17 Free Energy and Thermodynmics
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Tro, Chemistry: A Molecular Approach 2 First Law of Thermodynamics you can’t win! First Law of Thermodynamics: Energy cannot be Created or Destroyed the total energy of the universe cannot change though you can transfer it from one place to another E universe = 0 = E system + E surroundings
Background image of page 2
Tro, Chemistry: A Molecular Approach 3 First Law of Thermodynamics Conservation of Energy For an exothermic reaction, “lost” heat from the system goes into the surroundings two ways energy “lost” from a system, converted to heat, q used to do work, w Energy conservation requires that the energy change in the system equal the heat released + work done E = q + w E = H + P V E is a state function internal energy change independent of how done
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Tro, Chemistry: A Molecular Approach 4 Energy Tax you can’t break even! to recharge a battery with 100 kJ of useful energy will require more than 100 kJ every energy transition results in a “loss” of energy conversion of energy to heat which is “lost” by heating up the surroundings
Background image of page 4
Tro, Chemistry: A Molecular Approach 5 Thermodynamics and Spontaneity thermodynamics predicts whether a process will proceed under the given conditions spontaneous process nonspontaneous processes require energy input to go spontaneity is determined by comparing the free energy of the system before the reaction with the free energy of the system after reaction. if the system after reaction has less free energy than before the reaction, the reaction is thermodynamically favorable. spontaneity fast or slow
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Tro, Chemistry: A Molecular Approach 6 Comparing Potential Energy The direction of spontaneity can be determined by comparing the potential energy of the system at the start and the end.
Background image of page 6
Tro, Chemistry: A Molecular Approach 7 Reversibility of Process any spontaneous process is irreversible it will proceed in only one direction a reversible process will proceed back and forth between the two end conditions equilibrium results in no change in free energy if a process is spontaneous in one direction, it must be nonspontaneous in the opposite direction
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Tro, Chemistry: A Molecular Approach 8 Diamond
Background image of page 8
Image of page 9
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 27

pk 2 chem 6 - Chapter 17 Free Energy and Thermodynmics...

This preview shows document pages 1 - 9. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online