1st Semester Physical Chemistry Practice Final 2
1. Put a positive or negative sign next to each of the following to mark whether the entropy of the system increases or decreases during the following transformations: (2 points each) a. b. c. d. e. f. g. M
Please reread section 5.2 if you have problems with the equilibria problems. I will add a few more questions in a part two of the practice Final. I will be available during office hours and by appointment on non-furlough days prior to the final. To schedu
Physical Chemistry
The application of the principles and methods of physics and math to problems related to chemistry. A study of the physical principles underlying chemistry. (How and why materials behave the way they do) The ultimate goal of physical c
Department of Chemistry Seminar Series
Professor Jin Zhong Zhang Department of Chemistry University of California @ Santa Cruz
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Under many conditions, real gases do not follow the ideal gas law . - Intermolecular forces of attraction cause the measured
This lists important topics to study for the midterm. It is not necessarily a complete list of topics and is meant as a study guide only. The first Law of thermodynamics Extensive and Intensive Properties State functions Euler's test for State functions E
Practice Midterm Pchem 161A. Work in Small Groups. This is more material than will be in the in class test. A substantial portion of the in-class test will be taken from this practice midterm.
1) What are extensive and intensive properties. (1 point each
The First Law of Thermodynamics Thermodynamic transformations
Signs for heat (q) and work (w)
1
q is q is w is w is
+ +
if heat is added to system if heat is lost by system if work is done on the system. if work is done by the system.
2
System and Surrou
Name:_ Midterm 161A Fall Semester 2009 October 15 Show ALL of your WORK!
1) Which are extensive and intensive properties. (2 points) Circle the extensive variables: a) b) c) d) e) Volume Pressure Temperature Number of particles Energy
2) Circle which of t
The first Law of thermodynamics Extensive and Intensive Properties State functions Euler's test for State functions Exact and inexact differentials Ideal Gasses Van der Waals equation of state Reversible and Irreversible transformations Types of coupling
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State Variables
The Physical State of a system is completely described by a small number of Macroscopic Variables (N,V,T,U, concentrations. we will add more later on)
These variables are called state variables and include pressure, volume, temperature,
Ideal Gas Law
The combination of these three laws gives the ideal gas law which is a special form of an equation of state, i.e., an equation relating the variables that characterize a gas (pressure, volume, temperature, density, .). The ideal gas law is a
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Internal Energy of a Classical ideal gas
"Classical" means Equipartition Principle applies: each molecule has average energy kT per quadratic mode in thermal equilibrium.
q
At room temperature, for most gases: monatomic gas (He, Ne, Ar, .) 3 translation
1)
Show that the van der Waals pressure is a state function. a. First write down the differential dp given that the pressure is a function of Volume and temperature p(V,T) b. Apply Euler's method of mixed derivatives to show that dp is exact
2) Determine
Practice Midterm Pchem 161A. Work in Small Groups. This is more material than will be in the in class test. A substantial portion of the in-class test will be taken from this practice midterm.
1) What is are extensive and intensive properties. (1 point ea
Reversible Process
Grains of sand
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Remove one grain of sand at a time. Allow system to equilibrate Pressure decreases by very small amount Volume increases by very small amount. In limit of infinitesmal changes, system moves through equilibrium states du
Enthalpy
H U + PV - the enthalpy isochoric: isobaric: qv = U qp = H
in both cases, q does not depend on the path from 1 to 2.
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Energy is often described as the capacity to do work. PV also has the capacity to do work. (compressed air can power an engine
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Internal Energy of a Classical ideal gas
"Classical" means Equipartition Principle applies: each molecule has average energy kT per quadratic mode in thermal equilibrium.
q
At room temperature, for most gases: monatomic gas (He, Ne, Ar, .) 3 translation
T he Fi r st La w of T her modyna mi cs Thermodynamic transformations
Signs for heat (q) and work (w)
1
q is q is w is w is
+ +
if heat is added to system if heat is lost by system if work is done on the system. if work is done by the system.
2
System a
Carnot Cycle
We see that:
Th Vc = Tc Vb
-1
1
V = d V a
-1
Which means that
Vc Vb = Vd Va
Now also from the isothermal parts of the carnot cycle:
This is an important result. Temperature can be defined (on the absolute (Kelvin) scale) in terms of the