seacarb (version 3.2.14)

bjerrum: Bjerrum plot

Description

Plot the concentration of the various ionic forms of a molecule as a function of pH

Usage

bjerrum(K1=K1(), K2=NULL, K3=NULL, phmin=2, phmax=12, by=0.1, conc=1, 
     type="l", col="black",  ylab="Relative concentration (%)", add=FALSE, ...)

Arguments

K1

First dissociation constant

K2

Second dissociation constant, default is NULL

K3

Third dissociation constant, default is NULL

phmin

Minimum pH value, default is 2

phmax

Maximum pH value, default is 12

by

Increment on the pH axis, default is 0.1

conc

concentration of molecule, default is 1

type

Type of plot, default is line

col

Color of plot, default is black

ylab

Label of Y axis, default is (mol/kg)

add

false:start new, true: add to current, default is false

…

Graphical parameters (see par) and any further arguments of plot, typically plot.default, may also be supplied as arguments to this function. Hence, the high-level graphics control arguments described under par and the arguments to title may be supplied to this function.

Details

Note that the concentration is plotted in mol/kg only if conc is given is mol/kg

References

Zeebe, R. E. and Wolf-Gladrow D. A., 2001 CO2 in seawater: equilibrium, kinetics, isotopes. Amsterdam: Elsevier, 346 pp.

See Also

matplot, par, speciation.

Examples

# NOT RUN {
## Plot the bjerrum plot for the carbonate system using the default values
bjerrum(K1(),K2(),main="DIC speciation",lwd=2) 
abline(v=-log10(K1()),col="grey")
mtext(side=3,at=-log10(K1()),"pK1")
abline(v=-log10(K2()),col="grey")
mtext(side=3,at=-log10(K2()),"pK2")
legend("left",lty=1:3,lwd=2,legend=c(expression(CO[2]),expression(HCO[3]^"-"),
	expression(CO[3]^"2-")))

## Plot the bjerrum plot for phosphate using the default values
bjerrum(K1p(),K2p(),K3p(),main="phosphate speciation",lwd=2)
legend("left",lty=1:4,lwd=2,legend=c(expression(H[3]~PO[4]),
	expression(H[2]~PO[4]^"-"),
expression(HPO[4]^"2-"),expression(PO[4]^"3-")))

## Plot the bjerrum plot for the carbonate system using the values other 
##	than the default ones, showing the effect of temperature
bjerrum(K1(T=25,S=35),K2(T=25,S=35),conc=1.3,main="effect of temperature" )
bjerrum(K1(T=0,S=35),K2(T=0,S=35),conc=1.3,add=TRUE,col="red")
legend("left",lty=1,col=c("black","red"),legend=c("T=25 oC","T=0 oC"))
legend("right",lty=1:3,legend=c(expression(CO[2]),expression(HCO[3]^"-"),
	expression(CO[3]^"2-")))

## Plot the bjerrum plot for the carbonate system using the values other 
##	than the default ones, showing the effect of salinity
bjerrum(K1(T=25,S=35),K2(T=25,S=35),conc=1.3,main="effect of salinity" )
bjerrum(K1(T=25,S=5),K2(T=25,S=5),conc=1.3,add=TRUE,col="blue")
legend("left",lty=1,col=c("black","blue"),legend=c("S=35","S=5"))
legend("right",lty=1:3,legend=c(expression(CO[2]),expression(HCO[3]^"-"),
	expression(CO[3]^"2-")))

## Plot the bjerrum plot for the carbonate system using the values other 
##	than the default ones, showing the effect of pressure
bjerrum(K1(P=0),K2(P=0),conc=1.3,main="effect of pressure" )
bjerrum(K1(P=300),K2(P=300),conc=1.3,add=TRUE,col="green")
legend("left",lty=1,col=c("black","green"),legend=c("P=0","P=300"),title="atm")
legend("right",lty=1:3,legend=c(expression(CO[2]),expression(HCO[3]^"-"),
	expression(CO[3]^"2-")))
# }