Question

3. Estimate the fugacity and residual Gibb energy (GR) for n-butane at: (a) 350°K and 6 bar (b) 350°K and 14 bar The saturated vapor pressure of n-butane is 9.52 bar at 3500K.

Answer 1

) 350k and to bar From. Tc = 425-2k Pc = 38 bar W=0.199 / [cautical constants and Acenter factors for selected flauncher - Kayla lacewind psat = 9.52 bar This To = The 8.50 4252 0.823 Pr - Plec I Def30 8 6. = 0.157 9.52 38 For pure gas, -Pepsat - Ga P = 6 bar Lpsat so n-butane is vapour en bifr (B + WB) Tr B 0.083 - 0.422 Tolos -0-083 - 0.422 -0.4933 0.823

B'= 0.139 - 0-172 Tx 4.2 0.139-0-172 0.823 24-2 =-0-0959 Therefore en dat er ( 6+ we 0-157 0.636 0-4933 + +0.199x - 0.0959 59) 0823 =\0-139102 o o9 77 6: Q.6755 0.9068 Fuganity for a Pip 0.6755x6 o 6755x6 = 4.053 bar 0-9 068 X 6 5.44 bar

Gibbs fue energy Residual R Gi RT en Pi 9-314* 850*(-0.0147) 141.96 284.29 I (6) 350k and 14 bar psat, so n-bulane is bulane is liquid Now P = 14bar y Toko P= P/P 350 425.2 = 0.823 Sal 9.52 38 0-2505 0 -0.49 33.1 B B' - - 0.0959 } Aheady calidated and: Pr To [B'tw') 11 0.2505 0.82 3 [-00959 0-0959 + (0-199x-0-4933 -0.059 0-9426

di xpsal sal fi - & 0-9426x9.52 ~ 9 bar - 8.97 کی۔ RT en di = 8.314x3 50x ln 0.9426 172.6136]