5_60_lecture10

# 5_60_lecture10 - MIT OpenCourseWare http/ocw.mit.edu 5.60...

This preview shows pages 1–4. Sign up to view the full content.

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

View Full Document

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

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: MIT OpenCourseWare http://ocw.mit.edu 5.60 Thermodynamics & Kinetics Spring 2008 For information about citing these materials or our Terms of Use, visit: http://ocw.mit.edu/terms . 5.60 Spring 2008 Lecture #10 page 1 Entropy and Disorder • Mixing of ideal gases at constant T and p n A A (g, V A , T ) + n B A (g, V B , T ) = n (A + B) (g, V , T ) n V A n V B n V B spontaneous + n = n A B A B mixing V V + = A To calculate Δ S mix , we need to find a reversible path between the two states. constant T A B A + B piston piston back to initial state permeable permeable to A only to B only Δ S demix = −Δ S mix function of state For demixing process ⇒ Δ U = 0 ⇒ q = − w = p dV + p dV rev rev A A B B work of compression of each gas ∴ Δ S = dq rev = V A p A dV A + V B p B dV B = n R ln V A + n R ln V B demix ∫ T ∫ V T ∫ V T A V B V Put in terms of mole fractions X A = n A X B = n B n n Ideal gas ⇒ X A = V A X B = V B V V 5.60 Spring 2008 Lecture #10 page 2 ∴ Δ S demix =...
View Full Document

{[ snackBarMessage ]}

### Page1 / 5

5_60_lecture10 - MIT OpenCourseWare http/ocw.mit.edu 5.60...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online