1. Activity

2. AB composition ∆aG∆aG μoAμoA μoBμoB μ B = μ o B + RT. ln a B RT. ln a A RT. ln a B ΔG mix = x A. μ A + x B. μ B x A. μ o A + x B. μ o B x A. RT. ln a A + x B. RT. ln a B xBxB xAxA ΔG mix = x A. (μ o A + RT. ln a A ) + x B. (μ o B + RT. ln a B ) μ o A + RT. ln a A = μ A

3. Activity Al 2 O 3 SiO 2 Co Ky Sil And Bulk ∆aG∆aG Qz

4. Activity Co Ky Sil And Bulk ∆aG∆aG Qz Stable assemblage: Ky + Qz Al 2 O 3 SiO 2

5. Activity Co Ky Sil And Bulk ∆aG∆aG RT ln(a Co ) Qz Stable assemblage: Ky + Qz Al 2 O 3 SiO 2

6. Activity Co Ky Sil And Qz Bulk ∆aG∆aG Al 2 O 3 SiO 2

7. Activity Co Ky Sil And Qz Bulk ∆aG∆aG Qz* RT ln(a Qz ) Al 2 O 3 SiO 2

8. Activity Co Ky Sil And Qz Bulk ∆aG∆aG Qz* RT ln(a Qz ) Stable assemblage: Co + Qz* Al 2 O 3 SiO 2

9. Activity Co Ky Sil And Qz Bulk ∆aG∆aG Qz* RT ln(a Qz ) Stable assemblage: Co + Qz* Al 2 O 3 SiO 2 RT ln(a Ky )

10. Defining the Activity of H 2 O In database: add new phase 500 2000 1 SI(160)AL(60)NA(10)K(10)H(100)O(?) * In THERIN: STEAM06 H(2)O(1) H2O h2o ST CP1 COM STEAM[1] 0.6 "combination" Keywords + empty line activity There's always an easy solution to every human problem -- neat, plausible, and wrong. (Henry Louis Mencken)

11. Defining the Activity of H 2 O theriak ------------------- database definition ------------------- Enter [ "?" | CR | "files" | database filename ] ? --------------------------- define type of calculations --------------------------- Enter [ "?" | CR | "no" | "bin" | "loop" | filename ] ? Run theriak

12. Defining the Activity of H 2 O phase N mol% x ----- - ---- - 0 1 FSP_Ab 6.425745 4.107857 ALBITE 0.972798 K-FELDSPAR 0.027202 0 2 WHITE_MICA_Ms 13.574255 8.677762 MUSCOVITE 0.723812 PARAGONITE 0.276188 [Si(Z)] = 0.750000 [Al(Z)] = 0.250000 15 0 A-QUARTZ 93.574255 59.820239 23 0 ANDALUSITE 6.425745 4.107857 32 0 STEAM06 36.425745 23.286285 P 26 ALBITE 0.00000E+00 1.56423E+02 9.75960E-01 P 27 K-FELDSPAR 0.00000E+00 4.54481E+03 4.93115E-01 P 28 MUSCOVITE 0.00000E+00 1.84356E+03 7.50668E-01 P 29 PARAGONITE 0.00000E+00 1.99979E+03 7.32644E-01 P 30 JADEITE 0.00000E+00 2.18747E+04 3.32759E-02 P 31 STEAM 0.00000E+00 3.28369E+03 6.00000E-01 P 33 OXYGEN 0.00000E+00 4.89269E+05 8.80278E-34 S 63 FSP 0.00000E+00 0.00000E+00 1.00000E+00 9.7280E-01 2.7202E-02 S 67 WHITE MICA 0.00000E+00 -1.13687E-13 1.00000E+00 7.2381E-01 2.7619E-01 exit THERIAK CPU time: 0h 00m 00.04s

13. Defining the Activity of H 2 O Run domino JUN92.bs TC 500 900 P 1000 13000. 1 Run guzzler Run explot

14. Defining the Activity of H 2 O a(H 2 O) = 0.6

15. Defining the Activity of H 2 O a(H 2 O) = 1