Page 903 - Fundamentals of Water Treatment Unit Processes : Physical, Chemical, and Biological

858 Appendix H: Dissolved Gases

TABLE H.3
Henry’s Constant for Three Cases in Different Units

Compound Carbon Dioxide Oxygen Chloroform
Formula CO 2 O 2 CHCl 3
MW 44.0098 31.998 119.377
Form Units
Pa i(g) a a
9
9
Volatility—H D a 0.167 10 25 4.40 10 25
i
mol i(aq)=mol H 2 O
atm i(g) b 1510 20 c 43000 20 c 170 20 c
mol i(aq)=mol H 2 O d d
1212.2 25 227.84 25
mol i(g)=L(g) b 0.1905 20 b
mol i(aq)=LH 2 O
mol i(g)=mol(g) b
mol i(aq)=mol H 2 O
atm i(g) b,d,e d
3
mol i(aq)=m H 2 O 0.004101 25
e
0.00332 20
e
0.00421 25
f f f
Solubility—H S mol i(aq)=LH 2 O f 0.034 25 0.0013 25 0.27 25
1
atm i(g)
3
mol i(aq)=m H 2 O f,g
Pa
mg i(aq)=LH 2 O h h h f
1688–20 43.39–20 32231
atm i(g) d
29080
a
Alberty and Silbey (1992).
b
Brennan et al. (1998).
c
Kavanaugh and Trussell (1981).
d
Yaws (1999).
e
Ashworth et al. (1988).
f
Sander (1999).
g
Official SI unit according to Sander (1999).
h
This text; numerical values calculated from references indicated by footnotes.
Example H.6 Conversion of Henry’s Constant 2 18:01528 LH 2 O
3
S
as H in atm=mol Fraction to H in mg=L=atm ¼ 2:2784 10 atm CHCl 3 MW(CHCl) 998:21 10 mg
D
i
i
LH 2 O
D
1. Consider again, chloroform, CHCl 3 with H given 2
i ¼ 2:2784 10 atm CHCl 3 3
by Yaws (1999, p. 407). MW(CHCl) 55:51 10 mg
LH 2 O
atm 2
3
H D ¼ 2:2784 10 2 ¼ 2:2784 10 atm CHCl 3 119:377 55:51 10 mg
CHCl 3 ,25 C
mol fraction
atm CHCl 3 LH 2 O
2. Apply ‘‘labeling’’ of units and rounding off, ¼ 3:43 10 5
mg CHCl dissolved
3
S
H D ¼ 2:2784 10 2 atm CHCl 3 4. Convert to H , with rounding off in the final step,
CHCl 3 ,25 C mol CHCl 3 =mol H 2 O i
1
S
3. Now convert, by a chain of conversions, H CHCl 3 ,25 ¼ D
H
CHCl 3 ,25 C
atm CHCl 3 mol H 2 O
H D ¼ 2:2784 10 2 1
CHCl 3 ,20 C
mol CHCl 3 ¼ atm CHCl 3 LH 2 O
18:01528 g H O 3:43 10 5
mol CHCl 3
2 mg CHCl dissolved
MW(CHCl) g mol H 2 O
3

LH 2 O g 4 mg CHCl dissolved
3
¼ 2:9 10 atm CHCl 3
3
998:21 g H O(20 C) 10 mg LH 2 O
2