1 / 5

Understanding the 1st Law of Thermodynamics: Enthalpy, Heat Capacity, and Adiabatic Changes

Learn about constant pressure heat capacity, Cp vs. Cv, and calculations for CO2 heating. Explore the conceptual and mathematical aspects.

ygonzales
Download Presentation

Understanding the 1st Law of Thermodynamics: Enthalpy, Heat Capacity, and Adiabatic Changes

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. CHEM 433 – 9/30/11 III. 1st Law of Thermodynamics (Chapter 2) - Enthalpy, etc. (2.3-2.5) - Constant Pressure Heat Capacity (Cp) - Cp vs Cv - Adiabatic changes (2.6) READ: Keep reading Chapter #2… EXAM Ave = 40.5/50 = 81% (not bad …)

  2. Units on b must be K-1 ! ? ! ?

  3. Calculate H for constant pressure heating of CO2(1 mol) from 25°C to 50°C, assuming: Cp,m constant (= 37.11 J/K mol) Cp,m not constant, a, b, & c below…

  4. What is bigger - Cp or Cv? Why? 1) Conceptual Rationale: What happens when we add some amount of heat (q) to each system below? Const. V Const. p q q w=0 w≠0 T = TV T = TP The upshot … U and therefore T are less for the constant pressure system because the system can (and will) expand. Cp is BIGGER! 2) Mathematical: Can we calculate the difference: (Cp – Cv = …) for an ideal gas ?

More Related