HW4_Solution_key

# HW4_Solution_key - Problem 12-1 Raoult's equation for...

This preview shows pages 1–3. Sign up to view the full content.

Problem 12-1 Raoult’s equation for liquids, j vj j x p p = For binary mixtures: 1 1 2 2 1 2 1 v v x p x p p x x + = + = Multiplying second equation by - p v2 2 1 1 2 2 1 1 2 1 2 1 1 2 ( ) 1 v v v v v v v v v p p x p p p p x p p p p x x p p - - = - = - - = - = - For gas composition we should use Dalton’s equation in junction of Raoult’s equation 1 1 1 2 1 1 1 1 1 1 2 2 1 2 1 1 2 1 v v v v v v v v v v x p p p p x p y p y y p p p p p p p y y p p p - = = = - - = - = - Problem 12-6 Component Mass, lbs MW n Mol% Vapor pressure, psia Ki 2,2 dimethylbutane 3 86 0.0349 0.6654 9 1.8 2,2,4 trimethylpentane 2 114 0.0175 0.3346 1.7 0.34

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

View Full Document
n = 0.0349+0.0175 = 0.0524 lb mole Let A = 2,2 dimethylbutane and B = 2,2,4 trimethylpentane k A = P vA /P = 9/5 = 1.80 k B = P vB /P = 1.7/5 = 0.34 x A = (1-k B )/(k A -k B ) = (1-0.34)/(1.80-0.34) = 0.4521 x B = (k A -1)/(k A -k B ) = (1.8-1)/(1.80-0.34) = 0.5479 y A = k A x A = (1.8)(0.4521) = 0.8138 y B = k B x B = (0.34)(0.5479) = 0.1863 g n = n g /n = (z A -x A )/(y A -x A ) = (0.6654-0.4521)/(0.8138-0.4521) = 0.5897 ( 29 ( 29 g g n n n = =(0.5897)(0.0524) = 0.0309 lb mole of gas L n = n L /n = (y A -z A )/(y A -x A ) = (0.8138-0.6654)/(0.8138-0.4521) = 0.4103 ( 29 ( 29 L L n n n = = (0.4103)(0.0524) = 0.0215 lb mole of liquid M g = i i y M = (0.8138)(86)+(0.1863)(114) = 91.23 lb mass/lb mole M L = i i x M = (0.4521)(86)+(0.5479)(114) = 101.34 lb mass/lb mole m g = (n g )(M g ) = (0.0309)(91.23) = 2.82 lb mass of gas m L = (n L )(M L ) = (0.0215)(101.34) = 2.18 lb mass of liquid Problem 12-8. For bubble point temperature, we calculate P
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 8

HW4_Solution_key - Problem 12-1 Raoult's equation for...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online