CHAPTER 1 . Sea Water as an Electrolyte
25
plus-minus interactions represent the major ionic interactions that occur in the mixture. Once the cp for the mixture is estimated, a given physical property can be determined from:
p= pO + lPnr
(1.34)
For sea water, Eq. 1.33 can be broken down into terms for the individual major cations in the solution:
lP(SW) = ENacp(NaIXi) + EMgCP(MgIXi) + Ecacp(CaIXi) + EKCP(KIXi)
+ Esrcp(SrIXi)
(1.35)
The individual terms are given by:
cp(NaIXi) = ECl cp(NaCI) + E S04 CP(NazS04) + EHC03 cp(NaHC03) + EBrCP(NaBr)
+ EC03CP(NazC03) + EB(OH)4CP(Na(BOH)4) + EFCP(NaF)
(1.36)
Similar equations can be written for EMgCP(MgIXi),Ecacp(CaIXi), etc.
Since the apparent molal properties of individual electrolytes have been fitted to
equations of the form (Millero 1974,1975,2001):
cp(NaCI) = cpO(NaCI) + aII12 + bI + ...
(1.37)
(a, b etc. are empirical constants), the values for sea water or other natural waters
have the same form
lP(SW) = c.l,o(SW) + AJIIZ + BI + ...
(1.38)
where the individual terms are given by:
#(SW) = LMLXEMExt/P(MX)
(1.39)
A = LMLXEMExa(MX)
(1.40 )
B = LMLxEMExb(MX)
(1.41)
The superscript zero is to denote the values at infinite dilution or extrapolations to
pure water. These extrapolations yield parameters that are only due to the ion-water
interactions of the solution. The terms A and B are related to the ion-ion interactions
of the solution. Combining Eqs. 1.34 and 1.38 gives:
p = rfJ + A'I + B'I 3 • Z
(1.42)
where A' = AkI and B' = BkI (since nr = kI for a mixed electrolyte solution of fixed composition). This equation has been shown to reliably represent a number of physical
25
plus-minus interactions represent the major ionic interactions that occur in the mixture. Once the cp for the mixture is estimated, a given physical property can be determined from:
p= pO + lPnr
(1.34)
For sea water, Eq. 1.33 can be broken down into terms for the individual major cations in the solution:
lP(SW) = ENacp(NaIXi) + EMgCP(MgIXi) + Ecacp(CaIXi) + EKCP(KIXi)
+ Esrcp(SrIXi)
(1.35)
The individual terms are given by:
cp(NaIXi) = ECl cp(NaCI) + E S04 CP(NazS04) + EHC03 cp(NaHC03) + EBrCP(NaBr)
+ EC03CP(NazC03) + EB(OH)4CP(Na(BOH)4) + EFCP(NaF)
(1.36)
Similar equations can be written for EMgCP(MgIXi),Ecacp(CaIXi), etc.
Since the apparent molal properties of individual electrolytes have been fitted to
equations of the form (Millero 1974,1975,2001):
cp(NaCI) = cpO(NaCI) + aII12 + bI + ...
(1.37)
(a, b etc. are empirical constants), the values for sea water or other natural waters
have the same form
lP(SW) = c.l,o(SW) + AJIIZ + BI + ...
(1.38)
where the individual terms are given by:
#(SW) = LMLXEMExt/P(MX)
(1.39)
A = LMLXEMExa(MX)
(1.40 )
B = LMLxEMExb(MX)
(1.41)
The superscript zero is to denote the values at infinite dilution or extrapolations to
pure water. These extrapolations yield parameters that are only due to the ion-water
interactions of the solution. The terms A and B are related to the ion-ion interactions
of the solution. Combining Eqs. 1.34 and 1.38 gives:
p = rfJ + A'I + B'I 3 • Z
(1.42)
where A' = AkI and B' = BkI (since nr = kI for a mixed electrolyte solution of fixed composition). This equation has been shown to reliably represent a number of physical