Find the pH of water in equilibrium with atmospheric CO2 for the last 60 years, using the pCO2 atmospheric measurements below:
a. assuming T = 15°C
b. assuming T = 25°C and T = 30°C
pCO2
T (°C)
3.10E-04
15
3.50E-04
15
3.90E-04
15
3.10E-04
25
3.50E-04
25
3.90E-04
25
3.10E-04
30
3.50E-04
30
3.90E-04
30
Equilibrium constants as a function of T:
pK~pH~(-logioX) T(c) pKco2 pK [ pK_ pKcal pK _zg pKCalICO3+ pKCaco }
L,1 1.19 1.27 134 1.41 1.47 152 1.67 1.78 1.9 1.94
6.58
10.63
8.38 8.39
8.22
~0.82
33.13 3.13
6.52
10.55 10.49
8.24
-0.9
6.46
8.41
8.26
-0.97
3.3
6.42
10.43
8.43
8.28
-1.02
3.5
6.38
10.38
8.45
8.31
-1.07 ~II -1.14 -1.19 -1.23
33.18
6.35 6.33 6.29
10.33 10.29 10.2
8.48 8.51 8.62 8.76
8.34
33.22 33.27 3.45
8.37
8.49
6.29
10.14
8.64
33.65
6.34
10.13
8.99
8.88
-1.28
3.92
6.38
10.14
9.12
9.02
431
405