CHEM 433 – 10/7/11

III. 1st Law: “Machinery” (2.10)

- Properties of dU=

- Internal Pressure (T)

- Thermal Expansion Coefficient ()

- Properties of dH = (maybe?)

READ: FINISH CHAPTER 2

HW # 4 DUE

HW# 5 out today – Due Next F

For an Ideal gas: V(T,p) = nRT/p

Derive and expression for for an ideal gas.

€

=1

V

∂V

∂T

⎛

⎝ ⎜

⎞

⎠ ⎟p

An Illustration of the magnitude the effect of T:

Let’s assume that U= T,mV + Cv,mT

At 1.0 bar, heat 2.0°C, and compress by 100. cm3.

Cv,m = 27.3 J/mol KT= 840 Pa/mol

Calc U and compare terms (i.e. V vs. T):