1 / 4

Thermodynamics Primer (1/4)

Learn about the fundamentals of thermodynamics including energy, work, processes, laws, entropy, and Gibbs Free Energy in this comprehensive guide. Understand the principles behind physical and chemical changes of state, heat transfer, system dynamics, and more. Master the basics with clear explanations and key equations. Explore the laws that govern energy transformation and get an in-depth understanding of important concepts.

caesar
Download Presentation

Thermodynamics Primer (1/4)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Thermodynamics Primer (1/4) process: change of state: physical (e.g. melting, freezing, expansion) chemical (new substance formed) work: ability to change height of mass in surroundings i.e. transfer of energy that involves organized motion system: volume that we are interested in surroundings: everything else, where we make observations energy: capacity to do work heat: thermal form of energy; transfer of energy that makes use of chaotic motion of molecules endothermic: describes a process that absorbs energy exothermic: describes a process that releases energy internal energy U ≡ total energy of a system 1st Law: DU = q + w => the change in U is equal to the energy that passes through a system’s boundary as heat or work => the total energy of an isolated system is constant

  2. Thermodynamics Primer (2/4) enthalpy H ≡ U + PV Heat supplied at constant pressure (so long as the system does no additional work) heat capacity @ const. pressure cp ≡ (∂H/∂T)P Release of heat => a decrease in enthalpy of a system at const. pressure DH < 0 : exothermic DH > 0 : endothermic 2nd Law of Thermo: You can’t convert heat into work without some loss. direction of spontaneous change: toward a more disordered form (work not required) DStot > 0 (total entropy of an isolated system) => irreversible changes generate entropy => reversible changes do not generate entropy # of ways a system can be arranged to achieve same energy lvl S = k ln W k = 1.38 · 10-23 [J/K]

  3. Thermodynamics Primer (3/4) Thermodynamic Definition of entropy dS ≡ dq / T => DS = ∫dq / T Heat supplied at constant pressure (so long as the system does no additional work) 3rd law of thermo: at T = 0 K, all thermal motions cease => since S = k ln W , S = 0 ! Gibbs Free Energy: G=H-TS dG=dH-TdS-SdT H=U+PV dH=dU+PdV+VdP dG=dU+PdV+VdP-TdS-SdT dU=TdS-PdV dG=VdP-SdT Gibbs-Helmholz Eqn.: (T-dependence of GFE)

  4. Thermodynamics Primer (4/4) chemical potential of a substance j: (n’ : all other components) fundamental eqn. of thermodynamics: Always try to think in terms of G.F.E. to explain phenomena!

More Related